TW201240335A - Band-pass filter device and inductive module - Google Patents

Abstract

A band-pass filter device comprises: an input terminal for receiving input signals; an output terminal for providing output signals; one capacitor module electrically connected in between the input terminal and the output terminal of the band-pass filtering device, and the capacitor module includes at least two serially connected capacitors; and at least one inductive module having: a first end electrically connected to a common contact between the two capacitors; a grounded second end; a tapped inductor having a first end electrically connected to the first end of the inductive module, a second end electrically connected to the second end of the inductive module, and an intermediate tapping end; one transistor having a first end for receiving first bias voltage, a second end electrically connected to the second end of the intermediate tapping end, and a control terminal; and a feedback capacitor electrically connected between the control terminal of the transistor and the first end of the tapped inductor.

Description

201240335, invention description: TECHNICAL FIELD The present invention relates to a device and a module, and more particularly to a band pass filter device and an inductive module. [Prior Art] Bandpass filter devices with inductors and capacitors are used in radio electronics and consumer electronics to filter input signals at the front end of the product, but most bandpass filter devices do not use integrated components. The circuit is realized because the existing integrated circuitized inductor has a problem that the power consumption is too large in the CMOS process, and the quality factor (quality facr〇r) of the inductor is low. Therefore, in the integrated circuit, the active is often utilized. The device generates a negative resistance to compensate for the resistive loss of the inductor to improve the quality factor of the inductor. As shown in Figure 1 'in the literature' T. Soorapanth and S. S. Wong, "A0-dBIL2140 ± 30MHz bandpassfilterutilizing Q-reinforced spiral inductors in standard CMOS, '5 IEEE J. Solid-

State Circuits, vol. 37, no. 5, pp. 579-586, May 2002." A conventional bandpass filtering device 1' implemented in an integrated circuit and having a high quality factor is adapted to receive an input signal Vin And filtering to generate a filtered signal V〇, and the band pass filtering device 1 includes: first to third bias inductors RFC1 RFC1 to RFC3, first to third capacitors C1 to C3, an input capacitor Cin, and an output. Capacitor Co, and three inductive modules 11 to 13. The first to third bias inductors RFC1 to RFC3 each have a first end and a second end that receive a bias voltage VB. The first to third capacitors C1 - C3 each have a first end and a grounded 201240335 second end ' and the first ends of the first to third electric s C1 - C3 are electrically connected to the first to third respectively The second end of the bias inductors RFC 1 to RFC3. The input capacitor Cin has a first end receiving the input voltage vin and a second end electrically connected to the second end of the first bias inductor RFC1. The output capacitor Co has a first end that provides the filtered signal v〇 and a grounded second end. Each of the three inductive modules 11 to 13 has an input end and an output end. The input ends of the two inductive modules 11 , 12 and 13 are electrically connected to the second end of the first bias inductor RFC1, respectively. The second end of the second bias inductor RFC2 and the second end of the third bias inductor RFC3. The output ends of the three inductive modules 11 to 13 are electrically connected to the second end of the second bias inductor RFC2, the second end of the third bias inductor RFC3, and the first end of the output capacitor. Each of the inductive modules 11 to 13 has a transformer T, a transistor 14, and a capacitor C. The transformer τ has a primary side inductance L丨 and a secondary side inductance L2, and the primary and secondary side inductances li ' L2, the transistor 14 , and the capacitance C are connected in a feedback manner to make each inductive mode An input impedance Zin (see FIG. 2) at the input of the group 丨丨~^ generates a negative resistance effect, so that the inductive module 11 is equivalent to a semi-passive inductor having a high quality factor, and the input impedance Zin is (1) shown: Μ X gm^ 1

Zm = (R'—7Γ-) +... (1)

L C〇C where 'parameter R! is the parasitic resistance value of the primary side inductor L1,

4 S 201240335 The number M is the mutual inductance value between the secondary and secondary side inductors L1 and L2, and the parameter gm is the transconductance value of the electric solar body 14 (transc〇nductance), and the parameter [丨 is the angle of the second side Inductance value of the inductor L1, the parameter C is the capacitance value of the capacitor c, the parameter ω corner frequency 'the self-vibration frequency of the inductive module u is: during the low frequency band, 'there is a natural frequency is determined by the parameter c, and During the high frequency band, 'other-self-vibration frequency is determined by the parasitic capacitance generated by the overall layout. However, the conventional inductive mode group u and the band pass chopper device i have the following disadvantages: 1_ The transformer T is realized by the primary side inductance L1 and the secondary side inductance L2, requiring a large wafer area, resulting in Increased costs. 2. From the imaginary part of equation (1), it can be seen that during the low frequency band of the inductive module u from the direct current to the natural frequency, the imaginary part is negative, so it is capacitive, and only after the high frequency band exceeds the natural frequency. Inductive ten generations, so that the available frequency range is limited. 3. It can be seen from the formula (1) that the inductive module u as the equivalent inductance has only the inductance value of the primary side inductance L1, and the inductance value of the secondary side inductance L2 is not related, resulting in low utilization. 4_ From the real part of equation (1), it is known that the magnitude of the negative resistance of the inductive module u is only provided by (Mxgm/C), which will result in higher power consumption. 5. The band pass filter device 1 additionally requires a bias inductor rfc to provide a DC bias voltage, thereby increasing the hardware cost of the band pass filter device. 6. The size of the first to third capacitors C1 to C3 of the band-pass filter device cannot be dynamically adjusted, resulting in a fixed frequency response and limited use. 201240335 SUMMARY OF THE INVENTION Therefore, the first object of the present invention is to provide a band pass filtering device 0 that reduces cost, wide available frequency range, high utilization rate, and low power consumption. The band pass filtering device is suitable for receiving an input. Signaling and filtering to generate a filtered signal 'and the band pass filtering device comprises: an input for receiving the input signal; an output for providing the output signal; a capacitor module electrically connected to the band Between the input end of the wave device and the output 4, and the electric valley module includes at least two capacitors connected in series and at least one inductive module, having: a first end electrically connected between the two capacitors a common contact; a grounded second end; a first end electrically connected to the first end of the inductive module, and a second end electrically connected to the second end of the inductive module: - the tap An intermediate pumping between the first and second ends of the inductor: the end ^ W α π, one end, a Φ: the second end of the tap end of the tapped inductor, and the control terminal: the feedback capacitor, the electric Connected to the electro-crystalline inductor a control end between the end and the taper type 201240335 one-tap inductor having a _th-end, a grounded second end - a middle tap end between the first and second ends of the tapped inductor; a transistor having a first end of a receive-bias-bias, a second end connected to a center tap end of the tapped inductor, and a control terminal; and a control circuit electrically connected to the transistor Between the end and the first end of the tapped inductor. The above and other technical contents, features and effects of the present invention will be apparent from the following detailed description of the preferred embodiments. As shown in FIG. 3, a preferred embodiment of the bandpass filtering device of the present invention is adapted to receive an input signal and filter to generate a filtered signal and the bandpass filtering device includes: an input for receiving the input signal Vin An output terminal for providing the output signal Vo, a capacitor module 2, two inductive modules 3, and a variable capacitor module 4. <Capacitor Module> The electric valley module 3 is electrically connected between the input end and the output end of the band pass wave device to provide an equivalent capacitance value, and the capacitor module 3 includes three capacitors connected in series. In this embodiment, the three series capacitors are an input capacitor Cin, a coupling capacitor cb, and an output capacitor Co. The input capacitor Cin has a first end electrically connected to the input of the band pass filtering device to receive the input signal, and a second end. The surface capacitor Cb has a first end electrically connected to the second end 201240335 of the input capacitor Cin, and a second end. The output capacitor Co has a first end electrically connected to the second end of the coupling capacitor Cb, and a second end electrically connected to the output of the band pass filtering means to provide the filtered signal. <Inductive Modules> The two inductive modules 3 each have a first end electrically connected to the capacitor module 2 and a grounded second end, and the first ends of the two inductive modules 3 are respectively Electrically connected to the second end of the input capacitor Cin, the second end of the coupling capacitor cb, and each inductive module 3 has a tapped inductor TL, a transistor MOS, and two bypass capacitors C1 , C2, a feedback capacitor Cf, and a resistor r. The tapped inductor TL has a first end P1 electrically connected to the first end of the inductive module 3, a second end P3 electrically connected to the second end of the inductive module 3, and a tapped type A middle tap end P2, a first portion L1 and a second portion L2 in the middle of the first and second ends of the inductor. The first portion of the tapped inductor TL is electrically coupled to the first end of the tapped inductor TL? 1 is between the intermediate tap end P2. The second portion of the tapped inductor TL is electrically coupled between the second terminal P3 of the tapped inductor TL and the intermediate tap terminal p2. A transistor M0S has a first end that receives a first bias voltage of ¥1, and is electrically charged. Connected to the second end of the center tap end of the tapped inductor TL, and a control terminal. In this embodiment, the transistor is s-field-effect transistor, the first end is a pole, and the terminal is pole-phase. & secret, the controlled beta-resistor R has a first end of the receiving-second bias voltage V2, and a second terminal connected to the control terminal of the transistor MOS. The feedback capacitor Cf is electrically connected between the control terminal of the transistor m〇S and the first terminal of the tapped inductor TL. The two bypass capacitors C1 and C2 are electrically connected between the first end of the transistor M〇s and the ground between the first end of the resistor R and the ground. The equivalent impedance value Zin (see FIG. 4) between the first end and the second end of the tapped inductor TL includes a real part and an imaginary part, as shown by the formula (?), wherein the real part provides - Equivalent negative impedance value, and imaginary part provides - equivalent inductance value: Ζίη

(W Μ gm gm

C

C

) + jc〇(L'+L1+2M + Mm2i3i coC (2) ' "a \The first and second of the thermal god-type inductor TX: the equivalent series resistance value and parameter of U and L2. The value, M is the number of tapped inductors - and the mutual inductance between the second part, gm is the transduction value of the thre T vg 疋 亥 曰曰 曰曰 、 M 〇 、

The knife is the first of the tapped inductor TL - the number LI is determined by the parasitic capacitance generated by the electrical layout of the natural frequency of the inductive module 3. _ _ ' is a whole <variable capacitance module> The variable capacitance module 5 has an input terminal that receives a -T electrically connected to the second end of the input capacitor Cln and is connected to the CB terminal of the surface capacitance And the first output terminal of the variable capacitance module 5 provides a size correlation between the first and second output ends of the variable capacitance module 5 according to the change of the adjustment voltage Vc. The modulation frequency value of the adjustment voltage VC is used to change a center frequency and a frequency response of the band pass filter device, wherein a relationship between the modulation capacitance value and the adjustment voltage Vc is as follows (3) As shown in the figure, the center frequency is the equivalent capacitance value of the variable capacitance module 5, the equivalent inductance value of the two inductive modules 3, and the modulation capacitance value.

Cg =cmin +^Cg(l + tanh_~^Fc)... Equation (3) where Cg is the modulation capacitance value and Cmin is the minimum capacitance value of the layout structure 'Vc is the adjustment voltage, ^^ A voltage coefficient. dCg and , respectively, are the amount of change in the modulation capacitor value and the adjustment voltage. /〇=^fe··_...^ (4) where /〇 is the center frequency, Lp is the equivalent inductance value of the inductive module, and Cp is the equivalent capacitance value of the variable capacitance module 5. The variable capacitance module 5 further has a first diode D1, a second diode D2, a second diode D3' and a fourth diode D4. The first polar body D1 has a cathode electrically connected to the first output end of the variable capacitance module $ and an anode electrically connected to the wheel end of the variable capacitance module 5. ~8 5H The second diode D2 has a grounded cathode and an anode electrically connected to the input end of the capacitor 10 201240335 variable capacitance module 5. The 6th third diode D3 has a cathode electrically connected to the second output end of the variable capacitance module 5 and a 1% pole electrically connected to the wheel end of the variable capacitance module 5. The fourth body D4 has a grounded cathode and an anode electrically connected to the input end of the variable capacitance module 5. <Experimental Results> As shown in Fig. 5, the wafer layout of the tapped inductor TL shows that the first end P1, the intermediate tap end P2, and the second end P3 are all on the same side, so that it can be reduced. Long wiring and parasitic capacitance. As shown in FIG. 6, the quality factor of the inductive module 3 at different second bias voltages V2 can be seen as the second bias voltage V2 respectively & 〇v, 〇5, 0.56V, 〇.564V The corresponding maximum quality factor is 20.1, 52.3, and 124, respectively. 7 and 8, when the band-passing device operates at different adjustment voltages, the corresponding simulations S", S21 and the measurements S11, S21, wherein the parameters S1 and S21 are different from the reflection loss (return) Bss) and input loss (inSertl〇n 1〇SS) 'where the adjustment voltage VC is + 1V, - lv and the corresponding center frequency is 2 8GHZ, 2 5GHZ respectively. As shown in Fig. 9 by 7F', the band-pass filter is in the middle of 2.8 GHz and 2.5 GHz. The gain value obtained by the input power Pin is shown in Fig. 10. For the band, the filter is beneficial to the center frequency, which is • 8GHZ, 2.5GHZ, and the measured noise reduction ( Noise figure, NF) 201240335 'It can be seen that it is 6.3dB and 7.9dB respectively. It should be noted that in the embodiment, the band pass filtering device may include N inductive modules 3, and the capacitor module 2 may include N+1 series capacitors, where 'N21' is not limited to n. =2, and a common contact between any two of the N+1 series capacitors is electrically connected to the first end of the corresponding one of the N inductive modules 3. In summary, the above embodiment has the following advantages: 1_the tapped inductor TL is implemented by one inductor' and the conventional transformer has two inductors. Therefore, the tapped inductor TL is compared with the conventional one. The transformer requires only half of the wafer area. 2. It can be seen from the imaginary part of equation (2) that the imaginary part of the inductive module 3 is also positive and inductive during the low frequency range from direct current to the natural frequency, and thus has a larger available frequency band than conventional ones. range. 3. It can be seen from equation (2) that the equivalent inductance of the inductive module 3 is related to the total inductance value Ll+L2 of the tapped inductor TL, which has a better utilization ratio than the conventional one. 4. Comparing the formula (2) of the present case with the real part of the conventional formula (1), it is understood that the inductive module 3 of the present invention has a large negative resistance value and a small power consumption. 5. The band-pass filter device of the present invention does not require an additional bias inductor to provide a DC bias voltage, so the hardware cost of the band pass filter device can be reduced. In the conventional use, the variable capacitance module 5 is further used to adjust the frequency response of the band pass filter device, so that the use is more

S 12 201240335 wide. The above is only the preferred embodiment of the present invention, and the scope of the present invention is not limited thereto, that is, the simple equivalent changes and modifications made by the present invention in accordance with the scope of the invention and the description of the invention. : All are still within the scope of the invention patent. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a circuit diagram of a conventional band pass filter device; FIG. 2 is a conventional inductive module; FIG. 3 is a circuit diagram of a preferred embodiment of the band pass filter device of the present invention; 4 is a circuit diagram of a preferred embodiment of the inductive module of the present invention; FIG. 5 is a wafer layout diagram of the tapped inductor of the present invention; FIG. 6 is a quality factor corresponding to the different second bias voltages of the inductive module FIG. 7 is a first schematic diagram of the corresponding analog S", Sn and measurement Sn and Su when the band pass filter device is adjusted with different voltages; FIG. 8 is a schematic diagram of the band pass filter device when different voltages are adjusted. The corresponding schematic diagram of the simulated S", s21 and the measurement S丨丨, S2丨; Figure 9 is the bandpass filter at the center frequency of 2 8 GHz, 2-5 GHz, according to different input power A schematic diagram of the obtained gain value; and a graph ίο is a schematic diagram of the measured noise index when the center frequency is 2 8 GHz and 2.5 GHz, respectively. 13 201240335 [Explanation of main component symbols] 2 ........ Capacitor module C2 ···. •...Second capacitor Cin ... Input capacitor R....... •...Resistance Cb... ...Coupling Capacitor 5 ....... • Variable Capacitor Module Co ·...· Output Capacitor D1 ·····...First Diode 3 ....... Inductive Module D2 ···•...Second diode TL ····....Tap-type inductor D3 .... •...third diode L1 ····....the first part D4 ..... •...fourth diode L2 ·...·...the second part VI····...the first bias voltage P1...the first end V2 ·.....the second bias voltage P2... Intermediate tap end Vc .··. •...Adjust voltage P3.........Second end Vin...•...Input##MOS.·...Optosystem Vo.....·Output k#Cf.........Return capacitor C1 · ···. ...first capacitor

S 14

Claims (1)

201240335 VII. Patent application scope: 1. A bandpass chopper device, adapted to receive an input signal and filtered to generate a tear wave signal; and the bandpass wave device comprises: an input terminal for receiving the input An output terminal is configured to provide the output signal; a capacitor module electrically connected between the input end and the output end of the band pass filter device, and the capacitor module includes at least two capacitors γ connected in series The at least one inductive module has: a first end electrically connected to the _ common connection point between the two capacitors, and a grounded second end; the tapped inductor has an electrical connection to the inductive mode a first end of the first end of the group, a second end electrically connected to the second end of the inductive implant, and an imitation -t ^ is located at a middle tap end between the first and second ends of the tapped inductor a transistor having one connection and one electrical connection to the tapped inductor and a control terminal; and a first end of the first bias, a second end of the intermediate tap end, a feedback capacitor, and a tapped inductor First Patent application range based on the i-th inductive module further comprising: electrically connected between the control terminal of the transistor and the terminal. The band pass filtering device of the present invention, wherein a resistor has a first end receiving a first bias voltage and an electric 15 2. 201240335 is connected to a second end of the control end of the transistor; and a bypass capacitor, They are electrically connected between the first end of the transistor and the ground, and between the first end of the resistor and the ground. 3. The band pass filtering device according to claim 1, wherein the capacitor module comprises three capacitors, wherein the three capacitors are respectively: an input capacitor having an electrical connection The input end of the band pass filter device receives the first end of the input signal, and a second end; a coupling capacitor having a first end electrically connected to the second end of the input capacitor, and a second end; And an output capacitor having a first end electrically coupled to the second end of the coupling capacitor and a second end electrically coupled to the output of the bandpass filtering device to provide the filtered signal. 4. The band pass filter device according to claim 3, comprising two inductive modules, wherein the first ends of the two inductive modules are electrically connected to the second end of the input capacitor, respectively, and the coupling The second end of the capacitor. 5. The band pass filtering device according to claim 3, further comprising a variable electric valley module having an input end for receiving an adjusted voltage and a first output electrically connected to the second end of the input capacitor And a second output end electrically connected to the second end of the coupling capacitor, and the oscillating variable capacitance module is in the first and second rounds of the variable variable capacitance module according to the change of the adjustment voltage A modulation capacitor value of a magnitude related to the adjustment voltage is provided between the terminals. 16 201240335 6. The band-pass filter device according to claim 5, wherein the variable capacitor module further comprises: a first one body having an electrical connection to the first output end of the variable capacitance module Yin; 13⁄4 mouth __ often, by A 曰 ju bit and electrically connected to the variable capacitance module of the wheel (4), having a cathode and an anode electrically connected to the input end of the variable capacitance module; a third diode having a cathode electrically connected to the second output end of the variable capacitance module and an anode electrically connected to the input end of the variable capacitance module; and - a fourth two (four) having a grounding The cathode and the electrical connection are electrically connected to the anode of the wheeled end of the variable capacitance module. According to the scope of the patent application! The band pass wave device described in the item includes N inductive modules. The capacitor module includes n+i series capacitors 'where 'NM, and any two of the N+1 series capacitors A common contact is electrically connected to a corresponding one of the N inductive modules. 8. An inductive module comprising: and one end; a tapped inductor having a - first end, a grounded first a first end of the intermediate head between the first and second ends of the tapped inductor and an electrical second end, and a control transistor having a receiving first bias connected to the tapped inductor The end of the middle tap end; and 17 201240335 - the feedback capacitor 'electrically connected between the control end of the transistor and the first end of the pomelo inductor. 9. The inductive module of claim 8, wherein the inductive module further comprises: a resistor having a first end receiving a second bias, and an electrical connection to the electrical a second end of the control end of the crystal; and a bypass capacitor electrically connected between the first end of the transistor and the ground, between the first end of the resistor and the ground. 10. The inductive module according to claim 9, wherein the transistor is an N-type MOS field effect transistor, and the first end of the transistor is a drain, the transistor The second end is the source, and the control end of the transistor is the gate. S 18