[go: up one dir, main page]

US20040183606A1 - Oscillator circuit and L load differential circuit achieving a wide oscillation frequency range and low phase noise characteristics - Google Patents

Oscillator circuit and L load differential circuit achieving a wide oscillation frequency range and low phase noise characteristics Download PDF

Info

Publication number
US20040183606A1
US20040183606A1 US10/644,865 US64486503A US2004183606A1 US 20040183606 A1 US20040183606 A1 US 20040183606A1 US 64486503 A US64486503 A US 64486503A US 2004183606 A1 US2004183606 A1 US 2004183606A1
Authority
US
United States
Prior art keywords
inductance
circuit
input
switch
turned
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Abandoned
Application number
US10/644,865
Other languages
English (en)
Inventor
Hiroshi Komurasaki
Tomohiro Sano
Hisayasu Sato
Toshio Kumamoto
Yasushi Hashizume
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Renesas Technology Corp
Original Assignee
Renesas Technology Corp
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Renesas Technology Corp filed Critical Renesas Technology Corp
Assigned to RENESAS TECHNOLOGY CORP. reassignment RENESAS TECHNOLOGY CORP. ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: HASHIZUME, YASUSHI, KOMURASAKI, HIROSHI, KUMAMOTO, TOSHIO, SANO, TOMOHIRO, SATO, HISAYASU
Publication of US20040183606A1 publication Critical patent/US20040183606A1/en
Priority to US11/280,410 priority Critical patent/US7202754B2/en
Priority to US11/707,937 priority patent/US7362194B2/en
Abandoned legal-status Critical Current

Links

Images

Classifications

    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03B—GENERATION OF OSCILLATIONS, DIRECTLY OR BY FREQUENCY-CHANGING, BY CIRCUITS EMPLOYING ACTIVE ELEMENTS WHICH OPERATE IN A NON-SWITCHING MANNER; GENERATION OF NOISE BY SUCH CIRCUITS
    • H03B5/00—Generation of oscillations using amplifier with regenerative feedback from output to input
    • H03B5/18—Generation of oscillations using amplifier with regenerative feedback from output to input with frequency-determining element comprising distributed inductance and capacitance
    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03B—GENERATION OF OSCILLATIONS, DIRECTLY OR BY FREQUENCY-CHANGING, BY CIRCUITS EMPLOYING ACTIVE ELEMENTS WHICH OPERATE IN A NON-SWITCHING MANNER; GENERATION OF NOISE BY SUCH CIRCUITS
    • H03B5/00—Generation of oscillations using amplifier with regenerative feedback from output to input
    • H03B5/18—Generation of oscillations using amplifier with regenerative feedback from output to input with frequency-determining element comprising distributed inductance and capacitance
    • H03B5/1841—Generation of oscillations using amplifier with regenerative feedback from output to input with frequency-determining element comprising distributed inductance and capacitance the frequency-determining element being a strip line resonator
    • H03B5/1847—Generation of oscillations using amplifier with regenerative feedback from output to input with frequency-determining element comprising distributed inductance and capacitance the frequency-determining element being a strip line resonator the active element in the amplifier being a semiconductor device
    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03B—GENERATION OF OSCILLATIONS, DIRECTLY OR BY FREQUENCY-CHANGING, BY CIRCUITS EMPLOYING ACTIVE ELEMENTS WHICH OPERATE IN A NON-SWITCHING MANNER; GENERATION OF NOISE BY SUCH CIRCUITS
    • H03B5/00—Generation of oscillations using amplifier with regenerative feedback from output to input
    • H03B5/08—Generation of oscillations using amplifier with regenerative feedback from output to input with frequency-determining element comprising lumped inductance and capacitance
    • H03B5/12—Generation of oscillations using amplifier with regenerative feedback from output to input with frequency-determining element comprising lumped inductance and capacitance active element in amplifier being semiconductor device
    • H03B5/1206—Generation of oscillations using amplifier with regenerative feedback from output to input with frequency-determining element comprising lumped inductance and capacitance active element in amplifier being semiconductor device using multiple transistors for amplification
    • H03B5/1212—Generation of oscillations using amplifier with regenerative feedback from output to input with frequency-determining element comprising lumped inductance and capacitance active element in amplifier being semiconductor device using multiple transistors for amplification the amplifier comprising a pair of transistors, wherein an output terminal of each being connected to an input terminal of the other, e.g. a cross coupled pair
    • H03B5/1215—Generation of oscillations using amplifier with regenerative feedback from output to input with frequency-determining element comprising lumped inductance and capacitance active element in amplifier being semiconductor device using multiple transistors for amplification the amplifier comprising a pair of transistors, wherein an output terminal of each being connected to an input terminal of the other, e.g. a cross coupled pair the current source or degeneration circuit being in common to both transistors of the pair, e.g. a cross-coupled long-tailed pair
    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03B—GENERATION OF OSCILLATIONS, DIRECTLY OR BY FREQUENCY-CHANGING, BY CIRCUITS EMPLOYING ACTIVE ELEMENTS WHICH OPERATE IN A NON-SWITCHING MANNER; GENERATION OF NOISE BY SUCH CIRCUITS
    • H03B5/00—Generation of oscillations using amplifier with regenerative feedback from output to input
    • H03B5/08—Generation of oscillations using amplifier with regenerative feedback from output to input with frequency-determining element comprising lumped inductance and capacitance
    • H03B5/12—Generation of oscillations using amplifier with regenerative feedback from output to input with frequency-determining element comprising lumped inductance and capacitance active element in amplifier being semiconductor device
    • H03B5/1228—Generation of oscillations using amplifier with regenerative feedback from output to input with frequency-determining element comprising lumped inductance and capacitance active element in amplifier being semiconductor device the amplifier comprising one or more field effect transistors
    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03B—GENERATION OF OSCILLATIONS, DIRECTLY OR BY FREQUENCY-CHANGING, BY CIRCUITS EMPLOYING ACTIVE ELEMENTS WHICH OPERATE IN A NON-SWITCHING MANNER; GENERATION OF NOISE BY SUCH CIRCUITS
    • H03B5/00—Generation of oscillations using amplifier with regenerative feedback from output to input
    • H03B5/08—Generation of oscillations using amplifier with regenerative feedback from output to input with frequency-determining element comprising lumped inductance and capacitance
    • H03B5/12—Generation of oscillations using amplifier with regenerative feedback from output to input with frequency-determining element comprising lumped inductance and capacitance active element in amplifier being semiconductor device
    • H03B5/1237—Generation of oscillations using amplifier with regenerative feedback from output to input with frequency-determining element comprising lumped inductance and capacitance active element in amplifier being semiconductor device comprising means for varying the frequency of the generator
    • H03B5/124—Generation of oscillations using amplifier with regenerative feedback from output to input with frequency-determining element comprising lumped inductance and capacitance active element in amplifier being semiconductor device comprising means for varying the frequency of the generator the means comprising a voltage dependent capacitance
    • H03B5/1243—Generation of oscillations using amplifier with regenerative feedback from output to input with frequency-determining element comprising lumped inductance and capacitance active element in amplifier being semiconductor device comprising means for varying the frequency of the generator the means comprising a voltage dependent capacitance the means comprising voltage variable capacitance diodes
    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03B—GENERATION OF OSCILLATIONS, DIRECTLY OR BY FREQUENCY-CHANGING, BY CIRCUITS EMPLOYING ACTIVE ELEMENTS WHICH OPERATE IN A NON-SWITCHING MANNER; GENERATION OF NOISE BY SUCH CIRCUITS
    • H03B5/00—Generation of oscillations using amplifier with regenerative feedback from output to input
    • H03B5/08—Generation of oscillations using amplifier with regenerative feedback from output to input with frequency-determining element comprising lumped inductance and capacitance
    • H03B5/12—Generation of oscillations using amplifier with regenerative feedback from output to input with frequency-determining element comprising lumped inductance and capacitance active element in amplifier being semiconductor device
    • H03B5/1237—Generation of oscillations using amplifier with regenerative feedback from output to input with frequency-determining element comprising lumped inductance and capacitance active element in amplifier being semiconductor device comprising means for varying the frequency of the generator
    • H03B5/1256—Generation of oscillations using amplifier with regenerative feedback from output to input with frequency-determining element comprising lumped inductance and capacitance active element in amplifier being semiconductor device comprising means for varying the frequency of the generator the means comprising a variable inductance
    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03B—GENERATION OF OSCILLATIONS, DIRECTLY OR BY FREQUENCY-CHANGING, BY CIRCUITS EMPLOYING ACTIVE ELEMENTS WHICH OPERATE IN A NON-SWITCHING MANNER; GENERATION OF NOISE BY SUCH CIRCUITS
    • H03B5/00—Generation of oscillations using amplifier with regenerative feedback from output to input
    • H03B5/08—Generation of oscillations using amplifier with regenerative feedback from output to input with frequency-determining element comprising lumped inductance and capacitance
    • H03B5/12—Generation of oscillations using amplifier with regenerative feedback from output to input with frequency-determining element comprising lumped inductance and capacitance active element in amplifier being semiconductor device
    • H03B5/1237—Generation of oscillations using amplifier with regenerative feedback from output to input with frequency-determining element comprising lumped inductance and capacitance active element in amplifier being semiconductor device comprising means for varying the frequency of the generator
    • H03B5/1262—Generation of oscillations using amplifier with regenerative feedback from output to input with frequency-determining element comprising lumped inductance and capacitance active element in amplifier being semiconductor device comprising means for varying the frequency of the generator the means comprising switched elements
    • H03B5/1265—Generation of oscillations using amplifier with regenerative feedback from output to input with frequency-determining element comprising lumped inductance and capacitance active element in amplifier being semiconductor device comprising means for varying the frequency of the generator the means comprising switched elements switched capacitors
    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03B—GENERATION OF OSCILLATIONS, DIRECTLY OR BY FREQUENCY-CHANGING, BY CIRCUITS EMPLOYING ACTIVE ELEMENTS WHICH OPERATE IN A NON-SWITCHING MANNER; GENERATION OF NOISE BY SUCH CIRCUITS
    • H03B5/00—Generation of oscillations using amplifier with regenerative feedback from output to input
    • H03B5/08—Generation of oscillations using amplifier with regenerative feedback from output to input with frequency-determining element comprising lumped inductance and capacitance
    • H03B5/12—Generation of oscillations using amplifier with regenerative feedback from output to input with frequency-determining element comprising lumped inductance and capacitance active element in amplifier being semiconductor device
    • H03B5/1237—Generation of oscillations using amplifier with regenerative feedback from output to input with frequency-determining element comprising lumped inductance and capacitance active element in amplifier being semiconductor device comprising means for varying the frequency of the generator
    • H03B5/1262—Generation of oscillations using amplifier with regenerative feedback from output to input with frequency-determining element comprising lumped inductance and capacitance active element in amplifier being semiconductor device comprising means for varying the frequency of the generator the means comprising switched elements
    • H03B5/1268—Generation of oscillations using amplifier with regenerative feedback from output to input with frequency-determining element comprising lumped inductance and capacitance active element in amplifier being semiconductor device comprising means for varying the frequency of the generator the means comprising switched elements switched inductors

Definitions

  • the present invention relates to an oscillator circuit and an L load differential circuit, and particularly to an oscillator circuit using an LC resonant circuit as well as an L load differential circuit mountable on the oscillator circuit.
  • a local oscillator circuit is used for frequency conversion of received signals into low-frequency signals allowing demodulation and for frequency conversion of send signals (i.e., signals to be sent) into high-frequency signals, and is required to have a wide oscillation frequency range and can lower noises (phase noises) at and around an oscillation frequency.
  • a Voltage Control Oscillator which is a kind of local oscillator circuit, utilizes an oscillation phenomenon caused by positive feedback of the circuit, and can control the oscillation frequency by a control signal.
  • the VCO employs a resonant circuit or utilizes a delay time of a circuit.
  • a negative conductance LC oscillator circuit is known as an oscillator circuit utilizing negative resistance characteristics of a positive feedback circuit formed of transistors, as disclosed, e.g., in A. Yamagishi et al., “A Low-Voltage 6-GHz-Band CMOS Monolithic LC-Tank VCO Using a Tuning-Range Switching Technique”, IEICE Trans. Fundamentals, vol. E84-A, No. 2, February 2001. Since this oscillator circuit uses the LC resonant circuit including an inductor element and a capacitor element, it can achieve good phase noise characteristics, and application to VCOs for portable cordless devices has been expected.
  • a conventional VCO is formed of an LC resonant circuit formed of two inductor elements and two diode elements, and a positive feedback circuit formed of two transistors each having a gate connected to a drain of the other.
  • oscillation frequency f osc can be controlled in accordance with junction capacitance C var varied by the control voltage connected to the diode element.
  • An oscillation amplitude A osc of the VCO is expressed by the following formula (2), and takes the value proportional to oscillation frequency f osc .
  • the LC resonant circuit included in the VCO having the above differential structure is to be used for 1 to 2 GHz, an LC type using a lumped constant is predominantly employed because it can reduce an area of an integrated structure.
  • a variable capacitance (varactor diode) is predominantly used as the capacity element.
  • the inductor element is formed of a spiral inductance, which is formed of a spiral interconnection and a leader interconnection, and is generally formed on the same substrate as the transistor elements.
  • the inductance of the inductor element is uniquely determined in accordance with the form of the spiral, and cannot be adjusted unless a mask design is changed.
  • the transistor elements formed on the same substrate do not necessarily exhibit designed characteristics due to variations in manufacturing steps. Therefore, inductance mismatching occurs between the inductor elements, which reduces yield.
  • the inductance-variable element disclosed in Japanese Patent Laying-Open No. 7-142258 includes a spiral electrode formed on a semiconductor substrate with an insulating film therebetween and switch circuits for short-circuiting various turn portions of the spiral electrode.
  • oscillation frequency f osc in the conventional VCO is controlled by variable capacitance C var .
  • the equivalent parallel resistance of the LC resonant circuit lowers with increase in variable capacitance C var . Therefore, VCO may deviate from an oscillation state if the capacitance value is high. Accordingly, it is difficult to achieve a wide oscillation frequency range.
  • oscillation amplitude A osc of the VCO is proportional to oscillation frequency f osc .
  • oscillation amplitude A osc is low, and a signal-to-noise ratio of the oscillation signal is low so that the phase noise characteristics are impaired.
  • the foregoing inductance-variable element suffers from such a problem that the Q value lowers due to an on-resistance of a switch circuit connected in series to the inductor element. This results in deterioration of the phase noise characteristics of the oscillator circuit formed of the inductor element.
  • An object of the invention is to provide an oscillator circuit having a wide oscillation frequency range and characteristics achieving low phase noises.
  • Another object of the invention is to provide an L load differential circuit, which is mounted on the oscillator circuit, and achieves the above performance.
  • an oscillator circuit performs oscillation by positive feedback of an LC resonant circuit
  • the LC resonant circuit includes a parallel resonant circuit that is formed of an inductance-variable portion allowing variation of an inductance by a switch circuit and a capacitor element.
  • an oscillator circuit is formed of a pair of transistors cross-coupled to each other, and an LC resonant circuit of a differential type coupled to the pair of transistors in a feedback manner.
  • the LC resonant circuit includes first and second inductance-variable portions including first and second input/output terminals, commonly connected at their second terminals to a fixed node and being capable of varying inductances, and a first switch circuit coupled between the first input/output terminals of the first and second inductance-variable portions.
  • Each of the first and second inductance-variable portions has a spiral interconnection layer starting from the first input/output terminal and formed on a semiconductor substrate with an interlayer insulating film therebetween, and a plurality of second switch circuits having first terminals connected to arbitrary positions on the interconnection layer and second terminals commonly connected to the second input/output terminal, respectively.
  • the oscillator circuit electrically couples the connection position of the turned-on second switch circuit on the interconnection layer to the second input/output terminal.
  • the first switch circuit When the first switch circuit is turned on in response to the turn-on of the second switch circuit, the first switch circuit electrically couples the first and second inductance-variable portions.
  • the oscillation frequency of the oscillator circuit is controlled by varying the inductance of the LC resonant circuit, it is possible to achieve the oscillator circuit, which can prevent deterioration of the phase noise characteristics in a low oscillation frequency range, and can achieve a wide oscillation frequency range and characteristics ensuring low phase noises.
  • the two inductance-variable portions included in the differential LC resonant circuit are electrically coupled to form an inductor pair by the switch circuit arranged between the inductance-variable portions.
  • the switch circuit arranged between the inductance-variable portions.
  • FIG. 1 shows by way of example an oscillator circuit according to a first embodiment of the invention.
  • FIG. 2 schematically shows by way of example a structure of an inductance-variable portion.
  • FIG. 3 shows by way of example a structure of a switch circuit.
  • FIG. 4 is an equivalent circuit diagram of the inductance-variable portion in FIG. 2.
  • FIG. 5 shows a circuit structure of the voltage control oscillator circuit in FIG. 1 having inductance-variable portions Lvar 1 and Lvar 2 each formed of the inductance-variable portion shown in FIGS. 2 to 4 .
  • FIG. 6 schematically shows a structure of a first modification of the inductance-variable portion in FIGS. 2 and 4.
  • FIGS. 7 to 9 are circuit diagrams showing structures of second, third and fourth modifications of the inductance-variable portion shown in FIGS. 2 and 4, respectively.
  • FIG. 10 is a circuit diagram showing by way of example a structure of an oscillator circuit according to a second embodiment of the invention.
  • FIG. 11 is a circuit diagram showing by way of example a structure of an oscillator circuit according to a third embodiment of the invention.
  • FIG. 12 is a circuit diagram schematically showing a structure of a switch circuit group 1 in a voltage control oscillator circuit in FIG. 11.
  • FIG. 13 is an equivalent circuit diagram of switch circuit group 1 in FIG. 12.
  • FIG. 14 is an equivalent circuit diagram of switch circuit group 1 changed from ⁇ -connection to Y-connection shown in FIG. 13.
  • FIG. 15 shows a specific layout structure of inductance-variable portions Lvar 1 and Lvar 2 shown in FIG. 11.
  • FIG. 16 is a circuit diagram showing by way of example a structure of an oscillator circuit according to a modification of the third embodiment of the invention.
  • FIG. 1 shows a structure of an oscillator circuit according to a first embodiment of the invention.
  • a voltage control oscillator circuit will be described as an example of the oscillator circuit.
  • a voltage control oscillator circuit is formed of a differential type LC resonant circuit, which is formed of inductance-variable portions Lvar 1 and Lvar 2 having variable inductances and a capacitor element C 1 , and a positive feedback circuit formed of N-channel MOS transistors M 1 and M 2 .
  • Each of inductance-variable portions Lvar 1 and Lvar 2 has first and second input/output terminals, and the second input/output terminal is commonly connected to an external power supply node Vdd.
  • the first input/output terminals are connected to output nodes OUT and OUTB, respectively.
  • Capacitor element C 1 is connected between the first input/output terminals of inductance-variable portions Lvar 1 and Lvar 2 .
  • An oscillation frequency f osc of the voltage control oscillator circuit can be determined based on the inductance values of the inductance-variable portions and the capacitance value.
  • the positive feedback circuit includes N-channel MOS transistor M 1 electrically coupled between inductance-variable portion Lvar 1 and a constant current supply Ibias, and N-channel MOS transistor M 2 electrically coupled between inductance-variable portion Lvar 2 and constant current supply Ibias.
  • N-channel MOS transistors M 1 and M 2 have gates each coupled to a drain of the other, and thus provide a cross-coupled structure.
  • oscillation frequency f osc changes in accordance with inductance value L.
  • oscillation frequency f osc lowers with increase in inductance value L.
  • oscillation frequency f osc is lowered in accordance with increase in inductance value L, deterioration of oscillation amplitude A osc expressed in FIG. ( 4 ) is prevented. Therefore, it is possible to avoid deterioration of the phase noise characteristics, which occurs due to lowering of the oscillation amplitude in a conventional VCO when the oscillation frequency is in a low range.
  • FIG. 2 schematically shows by of example a structure of inductance-variable portions Lvar 1 and Lvar 2 . Since inductance-variable portions Lvar 1 and Lvar 2 have the same structure, FIG. 2 representatively shows only inductance-variable portion Lvar 1 .
  • inductance-variable portion Lvar 1 includes a spiral interconnection layer formed on a semiconductor substrate (not shown) with an interlayer insulating film therebetween, and switch circuits SW 1 -SW 3 .
  • the spiral interconnection layer is made of a metal material such as aluminum or copper, and the configuration thereof is not restricted to a square, and may be another form such as a polygon or a circle.
  • Switch circuits SW 1 -SW 3 have first terminals, which are connected to respective turns of the spiral interconnection layer, and second terminals connected to an input/output terminal of the inductor element. Switch circuits SW 1 -SW 3 receive control signals for controlling the turning-on/off thereof.
  • FIG. 3 shows by way of example a structure of switch circuits SW 1 -SW 3 .
  • switch circuit SWn may be formed of an N-channel MOS transistor 10 .
  • N-channel MOS transistor 10 When N-channel MOS transistor 10 is supplied with a control voltage Vsw as a control signal Sn on its gate, it is turned on or off depending on the voltage level of control voltage Vsw.
  • control voltage Vsw When control voltage Vsw is at a H-level (high potential level), N-channel MOS transistor 10 is turned on so that the corresponding portion of the spiral interconnection layer is electrically coupled to the input/output terminal of the inductor element.
  • control voltage Vsw When control voltage Vsw is at a L-level (low potential level), N-channel MOS transistor 10 is turned off. Thereby, the corresponding portion of the spiral interconnection layer is electrically isolated from the input/output terminal of the inductor element.
  • one of the switch circuits is selected to receive control voltage Vsw at the H-level, and the other switch circuits are supplied with control voltage Vsw at L-level so that an intended inductance value can be obtained.
  • switch circuits SW 1 -SW 3 are provided for the respective turns of the spiral interconnection layer, discrete inductance values can be obtained.
  • the N-channel MOS transistor is used as the switch circuit.
  • a bipolar transistor or a GaAs MESFET Metal Semiconductor Field-Effect Transistor
  • GaAs MESFET Metal Semiconductor Field-Effect Transistor
  • FIG. 4 is an equivalent circuit diagram of inductance-variable portion Lvar 1 in FIG. 2.
  • the inductance-variable portion is divided into three inductor elements L 1 , L 2 and L 3 by switch circuits SW 1 -SW 3 arranged for the respective turns. It is assumed that inductor elements L 1 , L 2 and L 3 have inductance values of L 1 , L 2 and L 3 , respectively.
  • switch circuit SW 1 when switch circuit SW 1 is on, the whole inductor elements have the inductance value of L 1 .
  • switch circuit SW 2 When switch circuit SW 2 is on, the whole inductor elements have the inductance value of (L 1 +L 2 ).
  • one of switch circuits SW 1 -SW 3 is turned on so that the inductance can selectively take the discrete values within a variable range from L 1 to (L 1 +L 2 +L 3 ).
  • FIG. 5 shows a circuit structure, in which each of inductance-variable portions Lvar 1 and Lvar 2 in the voltage control oscillator circuit shown in FIG. 1 employs the inductance-variable portion shown in FIGS. 2 to 4 .
  • inductance-variable portions Lvar 1 and Lvar 2 in the LC resonant circuit shown in FIG. 1 are expressed as the equivalent circuits shown in FIG. 4, and switch circuits SW 1 -SW 3 and SW 1 d -SW 3 d are arranged for the respective turns.
  • Capacitor element C 1 in the LC resonant circuit and the circuit structure of the positive feedback circuit are similar to those of the VCO in FIG. 1, and therefore, description thereof is not repeated.
  • Switch circuits SW 1 and SW 1 d form one switch circuit group.
  • switch circuits SW 2 and SW 2 d form one switch circuit group, and switch circuits SW 3 and SW 3 d form one switch circuit group.
  • one switch circuit group is selected from the three switch circuit groups, and switch circuits SWn and SWnd in the selected group are turned on.
  • the switch circuits in the other switch circuit groups are kept off.
  • each of inductance-variable portions Lvar 1 and Lvar 2 takes the inductance value of L 1 .
  • the inductance of the inductance-variable portion can be discretely varied within the variable range from L 1 to (L 1 +L 2 +L 3 ), as already described.
  • variable range of oscillation frequency f osc of the voltage control oscillator circuit can be expressed by the following formula (5): 1 2 ⁇ ⁇ ⁇ ( L 1 + L 2 + L 3 ) ⁇ ⁇ C ⁇ f osc ⁇ 1 2 ⁇ ⁇ ⁇ L ⁇ 1 ⁇ C ( 5 )
  • oscillation amplitude A osc does not deteriorate owing to increase in inductance L so that deterioration of phase noises does not occur.
  • the first embodiment of the invention can achieve the voltage control oscillator circuit having a wide oscillation frequency range and low-phase-noise characteristics, i.e., characteristics ensuring low phase noises.
  • the oscillator circuit of the first embodiment includes the LC resonant circuit employing the inductance-variable portion for improving the trade-off relationship between the variable oscillation frequency range and the phase noise characteristics.
  • the inductance-variable portion can easily provide various inductance values by switching the plurality of switch circuits provided for the spiral interconnection layer of the inductor element. A modification of the structure of the inductance-variable portion will now be described.
  • FIG. 6 schematically shows a structure of a first modification of inductance-variable portion Lvar 1 shown in FIGS. 2 and 4.
  • Inductance-variable portion Lvar 2 has the sane structure as inductance-variable portion Lvar 1 , and therefore description thereof is not repeated.
  • inductance-variable portion Lvar 1 includes switch circuits SW 1 -SW 4 arranged for quarters of the turn of the spiral interconnection layer, respectively, and thus has a structure achieved by adding a switch circuit to the inductor element in FIGS. 2 and 4.
  • an intended inductance can be likewise achieved by turning on one of switch circuits SW 1 -SW 4 . Further, by increasing the number of the switch circuits, it is possible to widen the variable range of the inductance value and to perform the control more finely.
  • FIG. 7 is an equivalent circuit diagram showing a structure of a second modification of inductance-variable portion Lvar 1 shown in FIGS. 2 and 4.
  • inductance-variable portion Lvar 1 includes switch circuits SW 4 and SW 5 in addition to switch circuits SW 1 -SW 3 arranged for respective turns in the equivalent circuit of the inductance-variable portion shown in FIG. 4.
  • Switch circuit SW 4 is arranged between input/output terminals 1 and 2 , and is connected in parallel with inductor elements L 1 -L 3 .
  • Switch circuit SW 5 is arranged between input/output terminal 1 and the terminal of switch circuit SW 2 , and is connected in parallel with inductor elements L 1 and L 2 .
  • switch circuits SW 1 -SW 5 are selectively turned on so that the inductance can be varied more finely in stepwise fashion. For example, when only switch circuit SW 1 is turned on, the inductance value of L 1 is achieved. When only switch circuit SW 2 is turned on, the inductance value is equal to (L 1 +L 2 ). Likewise, when switch circuit SW 3 is turned on, the inductance value is equal to (L 1 +L 2 +L 3 ).
  • the inductance can be finely varied by variously combining the on and off states of the plurality of switch circuits. Therefore, by employing the inductance-variable portion in FIG. 7 in the LC resonant circuit of the voltage control oscillator circuit shown in FIG. 1, it is possible to widen the variable frequency range of oscillation frequency f osc and to perform the control more finely.
  • FIG. 8 shows a structure of a third modification of inductance-variable portion Lvar 1 shown in FIGS. 2 and 4.
  • inductance-variable portion Lvar 1 includes switch circuits SW 4 -SW 9 in addition to switch circuits SW 1 -SW 3 provided for the respective turns in the equivalent circuit of the inductor element shown in FIG. 2.
  • Switch circuits SW 4 -SW 6 are connected in parallel with inductor elements L 1 -L 3 , respectively.
  • Switch circuit SW 7 is connected between one end of inductor element L 2 and one end of inductor element L 3 , and is arranged in parallel with inductor elements L 2 and L 3 .
  • Switch circuit SW 8 is connected between one end of inductor element L 1 and one end of inductor element L 2 , and is arranged in parallel with inductor elements L 1 and L 2 .
  • Switch circuit SW 9 is connected between one end of inductor element L 1 and one end of inductor element L 3 , and is arranged in parallel with inductor elements L 1 , L 2 and L 3 .
  • switch circuits SW 1 -SW 9 are selectively turned on so that the inductance can be controlled more finely that the inductance-variable portion shown in FIGS. 2 and 7.
  • the inductance can be determined more finely in the variation range by combining the on/off states of the plurality of switch circuits. Therefore, by employing the inductance-variable portion shown in FIG. 8 in the LC resonant circuit of the voltage control oscillator circuit in FIG. 1, it is possible to widen the variable frequency range of oscillation frequency f osc , and the control can be performed more finely.
  • FIG. 9 is a circuit diagram showing a structure of a fourth modification of inductance-variable portion Lvar 1 shown in FIG. 2.
  • inductance-variable portion Lvar 1 includes a plurality of inductor elements L 1 -L 3 having different inductances, respectively, and switch circuits SW 1 -SW 3 each coupled between one end of the spiral interconnection layer (not shown) of corresponding inductor element L 1 , L 2 or L 3 and the input/output terminal.
  • the inductance-variable portion in FIG. 2 has the plurality of switch circuits arranged for the one spiral interconnection layer.
  • the inductor element shown in FIG. 9 includes the switch circuits provided for the respective spiral interconnection layers in a one-to-one relationship. In the inductance-variable portion shown in FIG. 9, therefore, the inductance can be varied by turning on only the switch circuit, which corresponds to the inductor element having an intended inductance.
  • the inductance-variable portion having the above structure, the plurality of spiral interconnection layers are arranged in parallel, and therefore the circuit scale is large.
  • the switch circuit per one inductor element is small in number so that the circuit structure can be simple.
  • FIG. 10 shows by way of example an oscillator circuit according to a second embodiment of the invention. Similarly to the first embodiment, a voltage control oscillator circuit will be described as an example of the oscillator circuit.
  • the voltage control oscillator circuit differs from the voltage control oscillator circuit shown in FIG. 1 only in that the capacitor element forming the LC resonant circuit has a variable capacitance. Description of the same or corresponding portions is not repeated.
  • the LC resonant circuit is formed of inductance-variable portions Lvar 1 and Lvar 2 each connected between external power supply node Vdd and output node OUT or OUTB, and a variable capacitor element Cvar connected between first input/output terminals of inductor elements Lvar 1 and Lvar 2 .
  • each passive element has an inductance of L and a capacitance value of C.
  • oscillation frequency f osc of the voltage control oscillator circuit is expressed by the following formula (6), in which parasitic capacitances and others of each passive element, interconnection and others are ignored.
  • f osc 1 2 ⁇ ⁇ ⁇ L ⁇ ⁇ C ( 6 )
  • Oscillation amplitude A osc is expressed by the following formula (7).
  • oscillation frequency f osc depends on a combination of two variables, i.e., inductance L and capacitance value C. Therefore, the variable range of the oscillation frequency can be wider than that in the voltage control oscillator circuit of the first embodiment, in which only the inductance is variable.
  • the oscillation frequency can be lowered by increasing inductance L similarly to the first embodiment, deterioration of oscillation amplitude A osc can be suppressed even in the low oscillation frequency range. Thereby, deterioration of the phase noise characteristics at the low oscillation frequencies can be suppressed so that the trade-off relationship between the variable range of the oscillation frequency and the phase noises can be improved.
  • FIG. 11 shows a structure of an oscillator circuit according to a third embodiment of the invention.
  • a voltage control oscillator circuit will now be described as an example of an oscillator circuit.
  • the voltage control oscillator circuit includes switch circuits SW 1 dd -SW 3 dd arranged between inductance-variable portions Lvar 1 and Lvar 2 of the differential LC resonant circuit, in addition to the components of the voltage control oscillator circuit of the first embodiment shown in FIG. 5. Description of the same or corresponding portions is not repeated.
  • Inductance-variable portions Lvar 1 and Lvar 2 include switch circuits SW 1 -SW 3 or SW 1 d -SW 3 d arranged corresponding to the respective turns, similarly to inductance-variable portion Lvar 1 shown in FIG. 2.
  • a switch circuit SW 1 dd is arranged between switch circuits SW 1 and SW 1 d .
  • a switch circuit SW 2 dd is arranged between switch circuits SW 2 and SW 2 d .
  • a switch circuit SW 3 dd is arranged between switch circuits SW 3 and SW 3 d .
  • Switch circuits SW 1 , SW 1 d and SW 1 dd form one switch circuit group 1
  • switch circuits SW 2 , SW 2 d and SW 2 dd form a switch circuit group 2
  • switch circuits SW 3 , SW 3 d and SW 3 dd form one switch circuit group 3 .
  • FIG. 12 schematically shows a structure of switch circuit group 1 , 2 or 3 in the voltage control oscillator circuit shown in FIG. 11. Since the switch circuit groups 1 - 3 have the same structure, the structure of switch circuit group 1 will now be representatively described.
  • switch circuits SW 1 and SW 1 d are connected in parallel between external power supply node Vdd and inductor element L 1 . Further, switch circuit SW 1 dd is coupled between switch circuits SW 1 and SW 1 d.
  • one of the switch circuit groups is selected and turned on.
  • switch circuit group 1 when switch circuit group 1 is selected, switch circuits SW 1 , SW 1 d and SW 1 dd are turned on.
  • the inductance equal to L 1 is set in each of inductance-variable portions Lvar 1 and Lvar 2 arranged between external power supply node Vdd and respective output nodes OUT and OUTB.
  • inductance-variable portions Lvar 1 and Lvar 2 are in the state, where these portions are electrically coupled via switch circuit SW 1 dd .
  • An equivalent circuit of only switch circuit group 1 in this state is shown in FIG. 13.
  • a resistance element R is an on-resistance of each switch circuit.
  • each of the three resistance elements forming the equivalent circuit has a resistance value of R/3. Therefore, a resistance component, which is connected in series to each of the inductor elements included in inductance-variable portions Lvar 1 and Lvar 2 in FIG. 11, has a resistance value of R/3.
  • a resistance component connected in series to the inductor element has the resistance value of R equal to the on-resistance of switch circuits SW 1 -SW 3 and SW 1 d -SW 3 d .
  • interposition of switch circuits SW 1 dd -SW 3 dd reduces the resistance values of resistance components to 1 ⁇ 3.
  • the Q value of the LC resonant circuit has such characteristics that the Q value of the LC resonant circuit rises with decrease in resistance component connected in series to the inductor element, and lowers with increase in resistance component. Therefore, the resonant circuit in the voltage control oscillator circuit of this embodiment can have a higher Q value than the LC resonant circuit in FIG. 5 owing to the reduction in resistance component by switch circuits SW 1 dd -SW 3 dd . This results in low-phase-noise characteristics of the voltage control oscillator.
  • the differential LC resonant circuit thus constructed can be applied not only to the voltage control oscillator circuit of this embodiment, but also can be applied to an RF circuit such as a differential amplifier and a mixer, which has a differential LC resonant circuit as a load for achieving high-gain characteristics and low-noise characteristics owing to a high Q value.
  • the circuit may be used merely as an L load differential circuit in the RF circuit or the like, in which case a circuit having a variable gain can be achieved owing to the feature that the inductance value is variable.
  • FIG. 15 shows a specific layout structure of inductance-variable portions Lvar 1 and Lvar 2 in the differential LC resonant circuit included in the voltage control oscillator circuit shown in FIG. 11.
  • inductance-variable portions Lvar 1 and Lvar 2 form a differential inductance including a combination of two spiral interconnection layers.
  • Input/output terminal 1 common to the two inductance-variable portions is connected to external power supply node Vdd (not shown in FIG. 15).
  • Other input/output terminals 2 and 3 of the inductance-variable portions are connected to output nodes OUT and OUTB of the voltage control oscillator circuit (not shown in FIG. 15), respectively.
  • switch circuits SW 1 dd -SW 3 dd can be interposed without increasing the circuit scale, and thus the structure can be compact.
  • the two inductance-variable portions are electrically coupled by the switch circuits arranged therebetween to form the one inductor pair, and thereby the resistance component connected in series to the inductor element can be reduced so that deterioration of the Q value of the differential LC resonant circuit can be suppressed, and the voltage control oscillator circuit can have the characteristics ensuring low phase noises.
  • the inductor pair is formed of the differential type inductors. Thereby, it is possible to suppress increase in circuit scale, which may be caused by interposition of the switch circuits, and the voltage control oscillator circuit can be compact in layout.
  • FIG. 16 is a circuit diagram showing a structure of a voltage control oscillator circuit, which is an oscillator circuit according to a modification of the third embodiment of the invention.
  • the voltage control oscillator circuit differs from the voltage control oscillator circuit shown in FIG. 11 in that the inductor pair included in the differential LC resonant circuit is formed of inductance-variable portions Lvar 1 and Lvar 2 , each of which is formed of a plurality of inductor elements, and switch circuits SW 1 dd -SW 3 dd . Therefore, description of the portions corresponding to those of the voltage control oscillator circuit in FIG. 11 is not repeated.
  • the inductor pair is formed of two inductance-variable portions Lvar 1 and Lvar 2 , which are arranged in parallel and are connected to external power supply node Vdd, and switch circuits SW 1 dd -SW 3 dd arranged between inductance-variable portions Lvar 1 and Lvar 2 .
  • Inductance-variable portions Lvar 1 and Lvar 2 have the same structures as those shown in FIG. 9.
  • Inductance-variable portion Lvar 1 includes a plurality of inductor elements L 1 -L 3 , which are connected in parallel between external power supply node Vdd and output node OUT of the voltage control oscillator circuit, and have different inductances, respectively.
  • inductance-variable portion Lvar 1 includes switch circuits SW 1 -SW 3 coupled between respective inductor elements L 1 -L 3 and external power supply node Vdd.
  • inductance-variable portion Lvar 2 includes a plurality of inductor elements L 1 -L 3 , which are connected in parallel between external power supply node Vdd and output node OUTB of the voltage control oscillator circuit, and have different inductances, respectively, and switch circuits SW 1 d -SW 3 d coupled between respective inductor elements L 1 -L 3 and external power supply node Vdd.
  • an intended inductance can be achieved in each of inductance-variable portions Lvar 1 and Lvar 2 by turning on one of the plurality of switch circuits SW 1 -SW 3 or SW 1 d -SW 3 d.
  • the differential LC resonant circuit thus constructed can also be applied to an RF circuit such as a differential amplifier and a mixer, and thereby high-gain characteristics and low-noise characteristics can be achieved owing to the high Q value.
  • the circuit may be used merely as an L load differential circuit in the RF circuit or the like, in which case a circuit having a variable gain can be achieved owing to the feature that the inductance value is variable.
  • the oscillator circuit according to the invention can improve the trade-off relationship between the variable frequency range and the phase noise characteristics owing to the LC resonant circuit, which is configured to perform the control by the switch circuits arranged corresponding to the portions of the spiral interconnection layer, and thereby to provide the variable inductance values for controlling the oscillation frequency.
  • the differential LC resonant circuit includes the two inductance-variable portions, which are electrically coupled via the switch circuits to provide the inductor pair.
  • the resistance element connected in series to the inductor element is reduced, and the high Q value can be achieved.
  • the switch circuit may be formed of a transistor such as a Depletion-layer-Extended Transistor (which may be referred to as a “DTE”, hereinafter) capable of reducing an insertion loss, whereby the phase noise characteristics can be further improved.
  • a transistor such as a Depletion-layer-Extended Transistor (which may be referred to as a “DTE”, hereinafter) capable of reducing an insertion loss, whereby the phase noise characteristics can be further improved.
  • DTE Depletion-layer-Extended Transistor
  • the DTE has an element structure, which can be formed by removing a P-type well, P + -isolation layer and a punch-through stopper layer from a conventional CMOS transistor, and achieves a low junction capacitance of source/drain electrodes and a high ground resistance so that a low insertion loss can be achieved.
  • Specific element structures of the DTE are disclosed, e.g., in “A 1.4 dB Insertion-Loss, 5 GHz Transmit/Receive Switch Utilizing Novel Depletion-Layer-Extended Transistors (DETs) in 0.18 ⁇ m CMOS Process”, T. Ohnakado, et al., IEEE Symposium on VLSI Technology Digest of Tech. Papers, 16.4, June 2002.

Landscapes

  • Engineering & Computer Science (AREA)
  • Power Engineering (AREA)
  • Inductance-Capacitance Distribution Constants And Capacitance-Resistance Oscillators (AREA)
  • Filters And Equalizers (AREA)
US10/644,865 2003-03-04 2003-08-21 Oscillator circuit and L load differential circuit achieving a wide oscillation frequency range and low phase noise characteristics Abandoned US20040183606A1 (en)

Priority Applications (2)

Application Number Priority Date Filing Date Title
US11/280,410 US7202754B2 (en) 2003-03-04 2005-11-17 Oscillator circuit and L load differential circuit achieving a wide oscillation frequency range and low phase noise characteristics
US11/707,937 US7362194B2 (en) 2003-03-04 2007-02-20 Oscillator circuit and L load differential circuit achieving a wide oscillation frequency range and low phase noise characteristics

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
JP2003-056952(P) 2003-03-04
JP2003056952A JP4458754B2 (ja) 2003-03-04 2003-03-04 Ｌ負荷差動回路

Related Child Applications (1)

Application Number Title Priority Date Filing Date
US11/280,410 Division US7202754B2 (en) 2003-03-04 2005-11-17 Oscillator circuit and L load differential circuit achieving a wide oscillation frequency range and low phase noise characteristics

Publications (1)

Publication Number Publication Date
US20040183606A1 true US20040183606A1 (en) 2004-09-23

Family

ID=32958725

Family Applications (3)

Application Number Title Priority Date Filing Date
US10/644,865 Abandoned US20040183606A1 (en) 2003-03-04 2003-08-21 Oscillator circuit and L load differential circuit achieving a wide oscillation frequency range and low phase noise characteristics
US11/280,410 Expired - Fee Related US7202754B2 (en) 2003-03-04 2005-11-17 Oscillator circuit and L load differential circuit achieving a wide oscillation frequency range and low phase noise characteristics
US11/707,937 Expired - Fee Related US7362194B2 (en) 2003-03-04 2007-02-20 Oscillator circuit and L load differential circuit achieving a wide oscillation frequency range and low phase noise characteristics

Family Applications After (2)

Application Number Title Priority Date Filing Date
US11/280,410 Expired - Fee Related US7202754B2 (en) 2003-03-04 2005-11-17 Oscillator circuit and L load differential circuit achieving a wide oscillation frequency range and low phase noise characteristics
US11/707,937 Expired - Fee Related US7362194B2 (en) 2003-03-04 2007-02-20 Oscillator circuit and L load differential circuit achieving a wide oscillation frequency range and low phase noise characteristics

Country Status (6)

Country Link
US (3) US20040183606A1 (zh)
JP (1) JP4458754B2 (zh)
KR (1) KR100582796B1 (zh)
CN (1) CN100539396C (zh)
DE (1) DE10350512A1 (zh)
TW (1) TWI229975B (zh)

Cited By (15)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20040251978A1 (en) * 2003-06-13 2004-12-16 Nec Electronics Corporation Voltage controlled oscillator
US20060097811A1 (en) * 2004-11-09 2006-05-11 Takahiro Nakamura Variable inductor, and oscillator and communication system using the same
US20060232348A1 (en) * 2005-04-19 2006-10-19 Takuo Hino Inductor unit and oscillator using the inductor unit
US20060255872A1 (en) * 2005-05-12 2006-11-16 Takuo Hino Oscillator and a PLL circuit using the oscillator
US20070132522A1 (en) * 2005-12-08 2007-06-14 Lee Ja Y Multi-band LC resonance voltage-controlled oscillator with adjustable negative resistance cell
US20100295625A1 (en) * 2009-05-25 2010-11-25 Nec Electronics Corporation Variable inductor
US20110210799A1 (en) * 2007-04-26 2011-09-01 Mediatek Inc. Frequency Synthesizer
WO2015138105A1 (en) * 2014-03-11 2015-09-17 Qualcomm Incorporated LOW NOISE AND LOW POWER VOLTAGE-CONTROLLED OSCILLATOR (VCO) USING TRANSCONDUCTANCE (gm) DEGENERATION
US20160065130A1 (en) * 2014-08-27 2016-03-03 Soongsil University Research Consortium Techno-Park Oscillator with differential structure
US9812251B2 (en) 2013-12-18 2017-11-07 Taiwan Semiconductor Manufacturing Company, Ltd. Varainductor and operation method thereof based on mutual capacitance
CN111238544A (zh) * 2020-03-12 2020-06-05 江苏林洋能源股份有限公司 应用于温/湿度环境检测的基于lc型谐振器的微波传感器
WO2021097493A1 (en) * 2020-09-28 2021-05-20 Futurewei Technologies, Inc. Wideband low phase noise digitally controlled oscillator using switched inductors
US11025231B1 (en) * 2020-04-16 2021-06-01 Silicon Laboratories Inc. Providing a programmable inductor to enable wide tuning range
CN115498962A (zh) * 2022-11-16 2022-12-20 成都世源频控技术股份有限公司 一种低相位噪声晶体振荡器电路及实现方法
US11646705B2 (en) 2021-06-30 2023-05-09 Silicon Laboratories Inc. Dual-mode power amplifier for wireless communication

Families Citing this family (45)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR20060091507A (ko) * 2005-02-15 2006-08-21 삼성전자주식회사 병렬구조의 스위치드 가변 인덕터 회로
KR100698617B1 (ko) * 2005-02-15 2007-03-21 삼성전자주식회사 집적 인덕터를 포함한 집적회로
JP2007128985A (ja) * 2005-11-01 2007-05-24 Taiyo Yuden Co Ltd 可変インダクタ及びそれを用いたアンテナ装置
EP1788626B1 (en) * 2005-11-17 2009-04-29 Seiko Epson Corporation Multilayer circuit with variable inductor, and method of manufacturing it
KR100824783B1 (ko) * 2006-10-17 2008-04-24 삼성전자주식회사 다중 대역용 저잡음 증폭기 및 다중 대역용 무선 신호수신기
KR20080046941A (ko) * 2006-11-24 2008-05-28 동부일렉트로닉스 주식회사 능동 인덕터를 이용한 전압제어 발진기
JP2008288741A (ja) * 2007-05-16 2008-11-27 Japan Radio Co Ltd 帯域制限フィルタ
JP2009033643A (ja) * 2007-07-30 2009-02-12 Renesas Technology Corp 半導体集積回路
KR100935969B1 (ko) 2007-09-11 2010-01-08 삼성전기주식회사 광대역 전압 제어 발진기
JPWO2009041304A1 (ja) * 2007-09-28 2011-01-27 日本電気株式会社 発振回路
US8405467B2 (en) * 2007-11-27 2013-03-26 Qualcomm Incorporated Methods and apparatuses for inductor tuning in radio frequency integrated circuits
TWI353715B (en) * 2008-01-25 2011-12-01 Univ Nat Taiwan Inductive-switch, double-band, voltage-controlled
TW200950309A (en) * 2008-05-21 2009-12-01 Ralink Technology Corp Resonator circuit and voltage-controlled oscillator using the same
US7808266B2 (en) * 2008-12-31 2010-10-05 Texas Instruments Incorporated Method and apparatus for evaluating the effects of stress on an RF oscillator
US8063712B2 (en) * 2009-03-03 2011-11-22 Broadcom Corporation Method and system for voltage controlled oscillator impedance control to optimize performance, efficiency, and power consumption
KR101043668B1 (ko) * 2009-03-04 2011-06-24 한양대학교 산학협력단 능동 인덕터
US20110018646A1 (en) * 2009-07-27 2011-01-27 Electronics And Telecommunications Research Institute Lc voltage-controlled oscillator
US8842410B2 (en) * 2009-08-31 2014-09-23 Qualcomm Incorporated Switchable inductor network
JP2011101322A (ja) * 2009-11-09 2011-05-19 Renesas Electronics Corp 発振回路及び半導体装置
KR100982037B1 (ko) * 2009-12-14 2010-09-13 주식회사 아나패스 신호 생성 장치
JP5407842B2 (ja) * 2009-12-24 2014-02-05 富士通株式会社 可変インダクタおよびチューナブル高周波デバイス
US8319564B2 (en) * 2010-03-26 2012-11-27 Altera Corporation Integrated circuits with configurable inductors
CN102185562B (zh) * 2011-03-03 2012-11-21 西南大学 混沌振荡器及其作为随机比特发生器的应用
US8531250B1 (en) 2011-03-22 2013-09-10 Netlogic Microsystems, Inc. Configuring a tunable inductor across multiple layers of an integrated circuit
WO2012154098A1 (en) * 2011-05-11 2012-11-15 Telefonaktiebolaget L M Ericsson (Publ) A low noise oscillator
US8570111B2 (en) * 2011-11-02 2013-10-29 Realtek Semiconductor Corp. Single-staged balanced-output inductor-free oscillator and method thereof
KR101196842B1 (ko) * 2011-11-08 2012-11-01 숭실대학교산학협력단 나선형 인덕터를 이용한 ｌｃ 회로의 제어 장치
US9219452B2 (en) * 2012-05-22 2015-12-22 Intel Deutschland Gmbh Dual mode receiver with RF splitter using programmable passive components
US8860521B2 (en) * 2012-12-19 2014-10-14 Intel IP Corporation Variable inductor for LC oscillator
US9954488B2 (en) * 2013-03-15 2018-04-24 Taiwan Semiconductor Manufacturing Company, Ltd. Varainductor, voltage controlled oscillator including the varainductor, and phase locked loop including the varainductor
JP2015012571A (ja) * 2013-07-02 2015-01-19 ラピスセミコンダクタ株式会社 発振器及び位相同期回路
US9071193B1 (en) * 2013-10-16 2015-06-30 Cadence Design Systems, Inc. System and method for augmenting frequency tuning resolution in L-C oscillation circuit
US10270389B2 (en) * 2013-11-08 2019-04-23 Taiwan Semiconductor Manufacturing Company, Ltd. Semiconductor device and method
CN103633940B (zh) * 2013-11-21 2016-05-04 哈尔滨工业大学 一种有源电感型压控振荡器
JP5789003B2 (ja) * 2014-01-07 2015-10-07 ルネサスエレクトロニクス株式会社 発振回路及び半導体装置
US9444473B2 (en) * 2014-09-09 2016-09-13 Qualcomm Incorporated Increased synthesizer performance in carrier aggregation/multiple-input, multiple-output systems
TWI627646B (zh) * 2015-03-02 2018-06-21 瑞昱半導體股份有限公司 適用於振盪器之變壓器與其方法
US9425737B1 (en) 2015-03-16 2016-08-23 Futurewei Technologies, Inc. Tapped inductor voltage controlled oscillator
JP6471619B2 (ja) * 2015-06-12 2019-02-20 株式会社デンソー 電子装置
US20190189342A1 (en) * 2017-12-20 2019-06-20 National Chung Shan Institute Of Science And Technology Variable inductor and integrated circuit using the variable inductor
DE102018118724B4 (de) * 2018-08-01 2021-04-15 Infineon Technologies Ag Verfahren zum Programmieren einer einmalig programmierbaren Struktur, Halbleiterbauteil und Hochfrequenzbauteil
US11545985B2 (en) 2018-12-14 2023-01-03 Silicon Laboratories Inc. Apparatus for digitally controlled oscillators and associated methods
CN110098801B (zh) * 2019-06-13 2025-02-18 珠海微度芯创科技有限责任公司 压控振荡器
CN113395082B (zh) * 2021-06-21 2023-02-28 北京博瑞微电子科技有限公司 采用周期性开关电感负载传输线的频率可调时钟传输装置
JP7550806B2 (ja) * 2022-02-10 2024-09-13 大井電気株式会社 非接触給電用コイルおよび非接触給電用可変径コイル

Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4638263A (en) * 1983-10-07 1987-01-20 U.S. Philips Corporation Voltage controlled oscillator including two variable gain feedback circuits
US4670662A (en) * 1986-02-24 1987-06-02 Gt-Devices Pulse synthesizing network and method
US5872489A (en) * 1997-04-28 1999-02-16 Rockwell Science Center, Llc Integrated tunable inductance network and method
US6218909B1 (en) * 1998-10-23 2001-04-17 Texas Insturments Israel Ltd. Multiple frequency band voltage controlled oscillator
US6437653B1 (en) * 2000-09-28 2002-08-20 Sun Microsystems, Inc. Method and apparatus for providing a variable inductor on a semiconductor chip
US6593825B1 (en) * 2001-09-06 2003-07-15 Lsi Logic Corporation Oscillator having unidirectional current flow between resonant circuit and active devices
US6597248B2 (en) * 2000-06-19 2003-07-22 Nec Electronics Corporation Voltage-controlled oscillator
US20030146799A1 (en) * 2002-02-01 2003-08-07 Nec Electronics Corporation Voltage controlled oscillator
US6664863B1 (en) * 1999-07-26 2003-12-16 Niigata Seimitsu Co., Ltd.. LC oscillator

Family Cites Families (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2211987B (en) 1987-10-30 1992-01-02 Plessey Co Plc Circuit arrangement including an inductor and a mesfet
JP3318086B2 (ja) 1993-11-17 2002-08-26 新潟精密株式会社 インダクタンス可変素子
JPH08162331A (ja) 1994-12-05 1996-06-21 Hitachi Ltd 可変インダクタ及びそれを用いた半導体集積回路
JPH0935942A (ja) 1995-07-20 1997-02-07 Kokusai Electric Co Ltd ステップ可変型インダクタ
JPH11127028A (ja) 1997-10-21 1999-05-11 Alps Electric Co Ltd 平衡型発振器
WO2000076057A1 (de) 1999-06-05 2000-12-14 Institut für Halbleiterphysik Frankfurt (Oder) GmbH Spannungsgesteuerter oszillator mit lc-schwingkreis
KR20020084776A (ko) 2001-05-03 2002-11-11 마젤텔레콤 주식회사 다중밴드용 전압제어 발진기

Patent Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4638263A (en) * 1983-10-07 1987-01-20 U.S. Philips Corporation Voltage controlled oscillator including two variable gain feedback circuits
US4670662A (en) * 1986-02-24 1987-06-02 Gt-Devices Pulse synthesizing network and method
US5872489A (en) * 1997-04-28 1999-02-16 Rockwell Science Center, Llc Integrated tunable inductance network and method
US6218909B1 (en) * 1998-10-23 2001-04-17 Texas Insturments Israel Ltd. Multiple frequency band voltage controlled oscillator
US6664863B1 (en) * 1999-07-26 2003-12-16 Niigata Seimitsu Co., Ltd.. LC oscillator
US6597248B2 (en) * 2000-06-19 2003-07-22 Nec Electronics Corporation Voltage-controlled oscillator
US6437653B1 (en) * 2000-09-28 2002-08-20 Sun Microsystems, Inc. Method and apparatus for providing a variable inductor on a semiconductor chip
US6593825B1 (en) * 2001-09-06 2003-07-15 Lsi Logic Corporation Oscillator having unidirectional current flow between resonant circuit and active devices
US20030146799A1 (en) * 2002-02-01 2003-08-07 Nec Electronics Corporation Voltage controlled oscillator

Cited By (32)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US7547970B2 (en) 2003-06-13 2009-06-16 Nec Electronics Corporation Semiconductor device
US20040251978A1 (en) * 2003-06-13 2004-12-16 Nec Electronics Corporation Voltage controlled oscillator
US20060139114A1 (en) * 2003-06-13 2006-06-29 Nec Electronics Corporation Voltage controlled oscillator
US7088195B2 (en) * 2003-06-13 2006-08-08 Nec Electronics Corporation Voltage controlled oscillator having varactor and transistor regions underlying spiral conductors
US20090243110A1 (en) * 2003-06-13 2009-10-01 Nec Electronics Corporation Voltage controlled oscillator
US8502614B2 (en) 2004-11-09 2013-08-06 Renesas Electronics Corporation Variable inductor, and oscillator and communication system using the same
US7902934B2 (en) 2004-11-09 2011-03-08 Renesas Electronics Corporation Variable inductor, and oscillator and communication system using the same
US20110105053A1 (en) * 2004-11-09 2011-05-05 Renesas Electronics Corporation Variable inductor, and oscillator and communication system using the same
US20060097811A1 (en) * 2004-11-09 2006-05-11 Takahiro Nakamura Variable inductor, and oscillator and communication system using the same
US20060232348A1 (en) * 2005-04-19 2006-10-19 Takuo Hino Inductor unit and oscillator using the inductor unit
US7342464B2 (en) 2005-05-12 2008-03-11 Matsushita Electric Industrial Co., Ltd. Oscillator and a PLL circuit using the oscillator
US20060255872A1 (en) * 2005-05-12 2006-11-16 Takuo Hino Oscillator and a PLL circuit using the oscillator
US20070132522A1 (en) * 2005-12-08 2007-06-14 Lee Ja Y Multi-band LC resonance voltage-controlled oscillator with adjustable negative resistance cell
US7554416B2 (en) * 2005-12-08 2009-06-30 Electronics And Telecommunications Research Institute Multi-band LC resonance voltage-controlled oscillator with adjustable negative resistance cell
US20110210799A1 (en) * 2007-04-26 2011-09-01 Mediatek Inc. Frequency Synthesizer
US20100295625A1 (en) * 2009-05-25 2010-11-25 Nec Electronics Corporation Variable inductor
US8390386B2 (en) * 2009-05-25 2013-03-05 Renesas Electronics Corporation Variable inductor
US9812251B2 (en) 2013-12-18 2017-11-07 Taiwan Semiconductor Manufacturing Company, Ltd. Varainductor and operation method thereof based on mutual capacitance
US20150263671A1 (en) * 2014-03-11 2015-09-17 Qualcomm Incorporated LOW NOISE AND LOW POWER VOLTAGE-CONTROLLED OSCILLATOR (VCO) USING TRANSCONDUCTANCE (gm) DEGENERATION
US9634607B2 (en) * 2014-03-11 2017-04-25 Qualcomm Incorporated Low noise and low power voltage-controlled oscillator (VCO) using transconductance (gm) degeneration
US20170163214A1 (en) * 2014-03-11 2017-06-08 Qualcomm Incorporated LOW NOISE AND LOW POWER VOLTAGE-CONTROLLED OSCILLATOR (VCO) USING TRANSCONDUCTANCE (gm) DEGENERATION
WO2015138105A1 (en) * 2014-03-11 2015-09-17 Qualcomm Incorporated LOW NOISE AND LOW POWER VOLTAGE-CONTROLLED OSCILLATOR (VCO) USING TRANSCONDUCTANCE (gm) DEGENERATION
US10050586B2 (en) * 2014-03-11 2018-08-14 Qualcomm Incorporated Low noise and low power voltage-controlled oscillator (VCO) using transconductance (gm) degeneration
US20160065130A1 (en) * 2014-08-27 2016-03-03 Soongsil University Research Consortium Techno-Park Oscillator with differential structure
US9374035B2 (en) * 2014-08-27 2016-06-21 Soongsil University Research Consortium Techno-Park Oscillator with differential structure
CN111238544A (zh) * 2020-03-12 2020-06-05 江苏林洋能源股份有限公司 应用于温/湿度环境检测的基于lc型谐振器的微波传感器
US11025231B1 (en) * 2020-04-16 2021-06-01 Silicon Laboratories Inc. Providing a programmable inductor to enable wide tuning range
US11374555B2 (en) 2020-04-16 2022-06-28 Silicon Laboratories Inc. Providing a programmable inductor to enable wide tuning range
WO2021097493A1 (en) * 2020-09-28 2021-05-20 Futurewei Technologies, Inc. Wideband low phase noise digitally controlled oscillator using switched inductors
US11646705B2 (en) 2021-06-30 2023-05-09 Silicon Laboratories Inc. Dual-mode power amplifier for wireless communication
US12009793B2 (en) 2021-06-30 2024-06-11 Silicon Laboratories Inc. Dual-mode power amplifier for wireless communication
CN115498962A (zh) * 2022-11-16 2022-12-20 成都世源频控技术股份有限公司 一种低相位噪声晶体振荡器电路及实现方法

Also Published As

Publication number Publication date
KR20040078533A (ko) 2004-09-10
US20070146089A1 (en) 2007-06-28
JP4458754B2 (ja) 2010-04-28
KR100582796B1 (ko) 2006-05-23
JP2004266718A (ja) 2004-09-24
DE10350512A1 (de) 2004-10-07
US7202754B2 (en) 2007-04-10
TWI229975B (en) 2005-03-21
TW200418260A (en) 2004-09-16
CN100539396C (zh) 2009-09-09
CN1527476A (zh) 2004-09-08
US20060071732A1 (en) 2006-04-06
US7362194B2 (en) 2008-04-22

Similar Documents

Publication Publication Date Title
US7362194B2 (en) Oscillator circuit and L load differential circuit achieving a wide oscillation frequency range and low phase noise characteristics
US7088195B2 (en) Voltage controlled oscillator having varactor and transistor regions underlying spiral conductors
US8305151B2 (en) Resonance type oscillation circuit and semiconductor device
EP1261126A2 (en) Varactor based differential VCO with switchable frequency bands
US6661301B2 (en) Oscillator circuit
US20040080374A1 (en) Voltage controlled oscillator
US11228280B1 (en) Microelectromechanical system resonator-based oscillator
US7375596B2 (en) Quadrature voltage controlled oscillator
US9035708B2 (en) Low noise voltage controlled oscillator
US8098109B2 (en) Differential varactor circuit for a voltage controlled oscillator
KR101759780B1 (ko) 전압 제어 오실레이터를 위한 시스템 및 방법
JP2002151953A (ja) 電圧制御発振器の周波数切替え装置
US20040150485A1 (en) Voltage controlled oscillator
JP4669130B2 (ja) 発振装置
US20050206465A1 (en) Voltage control oscillator
Seshan et al. Design of low power 2.4 GHz CMOS LC oscillators with low phase-noise and large tuning range
JP2012253561A (ja) 電圧制御発振器
US11831278B2 (en) Voltage-controlled oscillator device
KR101834245B1 (ko) 저 위상잡음 특성을 갖는 다중대역 ｃｍｏｓ ｌｃ ｖｃｏ 회로
US6781482B2 (en) Integrated circuit
US6593825B1 (en) Oscillator having unidirectional current flow between resonant circuit and active devices
US20240388251A1 (en) Quadrature oscillator
Maheshwari et al. Design & optimization of switched capacitor array based differential CMOS LC VCO for wide band application
JP2005236482A (ja) Ｌｃ発振器
Vibhute et al. MEMS components for front end of direct conversion receiver architecture

Legal Events

Date Code Title Description
AS Assignment

Owner name: RENESAS TECHNOLOGY CORP., JAPAN

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:KOMURASAKI, HIROSHI;SANO, TOMOHIRO;SATO, HISAYASU;AND OTHERS;REEL/FRAME:014424/0339

Effective date: 20030714

STCB Information on status: application discontinuation

Free format text: ABANDONED -- FAILURE TO RESPOND TO AN OFFICE ACTION