TWI522985B - Charge pump circuit - Google Patents

Description

Charge pump circuit

This invention relates to a charge pumping circuit and, more particularly, to a charge pumping circuit for a display.

Please refer to FIG. 1. FIG. 1 is a schematic circuit diagram of a charge pump circuit according to a conventional one. As shown in FIG. 1, the charge pump circuit 9 is a charge pump circuit conventionally used in the field of display. The charge pump circuit 9 is mainly used to generate a low-level gate voltage. VGL) and high-level gate voltage (also known as VGH). The gate turn-on voltage VGH is mainly generated by the capacitors C2~C6 and the diodes D1~D4 in the voltage level generating module 90, and the gate turn-off voltage VGL is mainly generated by the voltage level generating module 90. Capacitors C7~C9 and diodes D5~D6 are produced. In addition, the input voltage Vin can generate a power analog voltage AVDD through the inductor L1, the diode D1 and the capacitor C1, and the power analog voltage AVDD is a voltage supplied to the source driver. The pulse width modulation integrated circuit 90 includes a voltage regulator 920 and a transistor M1.

Please refer to FIG. 2, which is a circuit diagram of another charge pumping circuit according to a conventional one. In order to save the number of diodes used in the charge pump circuit, current display manufacturers will utilize a plurality of switchers SW1~SW6. The diodes are replaced, and these switches SW1 to SW6 are packaged in the pulse width modulation integrated circuit 90' as shown in Fig. 2. The gate-off voltage VGL generated by the charge pump circuit 9' is mainly transmitted through the first voltage regulator 902' and the switch SW1 in the first voltage level generating module 900', the switch SW2, the capacitor C1 and the capacitor. Produced by C2. On the other hand, the gate-on voltage VGH generated by the charge pump circuit 9' is mainly transmitted through the second voltage regulator 906' and the switch SW3 and the switch SW4 in the second voltage level generating module 904'. The switch SW5, the switch SW6, the capacitor C3, the capacitor C4, the capacitor C5, and the capacitor C6 are generated.

It can be observed from FIG. 2 that the first voltage level generating module 900' needs to generate a gate turn-off voltage VGL with a voltage level of -AVDD through one stage of charge pumping, and the second voltage level generating module 904. 'The two-stage charge pumping is required to generate the gate-on voltage VGH with a voltage level of +3 AVDD, so that the entire charge pumping circuit 9' requires three stages of charge pumping, resulting in an increase in manufacturing cost.

In view of the above problems, the present disclosure proposes a charge pumping circuit that reduces the number of charge pumping stages in a charge pumping circuit through a new charge and discharge path.

According to an embodiment of the present disclosure, a charge pumping circuit includes a first voltage level generating module and a second voltage level generating module. The first voltage level generating module has a first output end, and the first voltage level generating module includes a first capacitor, a second capacitor, and a first switch group. One end of the second capacitor is coupled to the first output end. The first switch group is configured to selectively switch to turn on the first power The flow path and the second current path. The first capacitor stores a first predetermined voltage when the first current path is turned on. When the second current path is turned on, the first capacitor is coupled in series with one end of the second capacitor, and the terminal voltage of the second capacitor coupled to the one end of the first output terminal is pulled to a second preset voltage. The second voltage level generating module has a second output end, and the second voltage level generating module includes a third capacitor, a fourth capacitor, and a second switch group. One end of the fourth capacitor is coupled to the second output end. The second switch group is configured to selectively switch between the third current path and the fourth current path. When the third current path is turned on, the third capacitor stores a third preset voltage, where the third preset voltage is a voltage difference between the first preset voltage and the fourth preset voltage. When the fourth current path is turned on, the third capacitor is coupled in series with one end of the fourth capacitor, and the terminal voltage of the fourth capacitor coupled to the end of the third capacitor is pulled to the first preset voltage and the third preset voltage. The sum of the voltages.

In one embodiment, the second preset voltage is a reverse first preset voltage, and the fourth preset voltage is a second preset voltage. When the second current path is turned on, the voltage level output by the first output terminal is a reverse first predetermined voltage. When the fourth current path is turned on, the voltage level output by the second output terminal is three times the first preset voltage.

According to an embodiment of the present disclosure, a charge pumping circuit includes a first voltage level generating module and a second voltage level generating module. The first voltage level generating module has a first output end, and the first voltage level generating module includes a first capacitor, a second capacitor, and a first switch group. One end of the second capacitor is coupled to the first output end. The first switch group is configured to selectively switch between the first current path and the second current path. The first capacitor is stored when the first current path is turned on There is a first preset voltage. When the second current path is turned on, the first capacitor is coupled in series with one end of the second capacitor, and the terminal voltage of the second capacitor coupled to one end of the first capacitor is pulled to a second preset voltage. The second voltage level generating module has a second output end, and the second voltage level generating module includes a third capacitor, a first diode, a second diode, a fourth capacitor, and a second switch group. The anode of the first diode is coupled to the first predetermined voltage, and the cathode of the first diode is coupled to the first end of the third capacitor. The anode of the second diode is coupled between the first end of the third capacitor and the cathode of the first diode, and the cathode of the second diode is coupled to the second output. The fourth capacitor is coupled between the cathode of the second diode and the second output end. The second switch group is configured to selectively switch between the third current path and the fourth current path. When the third current path is turned on, the terminal voltage of the fourth capacitor coupled to the one end of the second output terminal is pulled to the first preset voltage. When the fourth current path is turned on, the second end of the third capacitor is coupled to the third preset voltage, so that the voltage level output by the second output terminal is twice the first preset voltage and the third preset voltage. Voltage difference.

In one embodiment, the second preset voltage is a reverse first preset voltage, and the third preset voltage is a second preset voltage. When the second current path is turned on, the voltage level output by the first output terminal is a reverse first predetermined voltage. When the fourth current path is turned on, the voltage across the third capacitor is a voltage difference between the first predetermined voltage and the third predetermined voltage.

In summary, the present disclosure provides a charge pumping circuit that transmits a first switch group in a first voltage level generating module and a second switch group in a second voltage level generating module. Selectively conduct different current paths The first output end of the first voltage level generating module and the second output end of the second voltage level generating module can be made by the charge and discharge characteristics of the plurality of capacitors in different current paths. Two different voltage levels are output separately. In addition, the second voltage level generating module can further generate a corresponding output voltage according to the voltage output by the first output end of the module according to the first voltage level.

The above description of the disclosure and the following description of the embodiments of the present invention are intended to illustrate and explain the spirit and principles of the invention, and to provide further explanation of the scope of the invention.

1, 1', 9, 9' ‧ ‧ charge pump circuit

10, 900'‧‧‧First voltage level generation module

100‧‧‧First switch group

12, 902'‧‧‧First Voltage Regulator

14, 14', 904'‧‧‧ second voltage level generation module

140, 140’‧‧‧second switch group

16, 906’‧‧‧Second voltage regulator

92, 90'‧‧‧ pulse width modulation integrated circuit

920‧‧‧Voltage regulator

V1, V _X , V _X '‧‧‧ preset voltage

Vin‧‧‧Input voltage

AVDD‧‧‧ power analog voltage

VGH‧‧‧ gate conduction voltage

VGL‧‧‧ gate cutoff voltage

C1~C9‧‧‧ capacitor

D1~D6‧‧‧ diode

SW1~SW6, SW3'‧‧‧ switch

M1‧‧‧O crystal

L1‧‧‧Inductance

a, b‧‧‧ switching node

Output_1‧‧‧first output

Output_2‧‧‧second output

I1~I4‧‧‧ current path

T0~t3, t0’~t3’‧‧‧

Figure 1 is a circuit diagram of a charge pump circuit according to one of the conventional ones.

Figure 2 is a circuit diagram of another charge pumping circuit in accordance with the prior art.

3 is a circuit diagram of a charge pumping circuit in accordance with an embodiment of the present disclosure.

Fig. 4A is a schematic diagram showing the operation mode of the circuit when the charge pump circuit according to Fig. 3 is turned on the first current path.

4B is a schematic diagram of a circuit operation mode when the charge pump circuit according to FIG. 3 is turned on the second current path.

Fig. 4C is a schematic diagram showing the circuit operation mode when the charge pump circuit according to Fig. 3 is turned on the third current path.

4D is a schematic diagram of a circuit operation mode when the charge pump circuit according to FIG. 3 is turned on the fourth current path.

Figure 5A is a timing diagram of the module generated according to the first voltage level of Figure 3.

Figure 5B is a timing diagram of the module generated according to the second voltage level of Figure 3.

Figure 6 is a circuit diagram of a charge pumping circuit in accordance with another embodiment of the present disclosure.

The detailed features and advantages of the present invention are set forth in the Detailed Description of the Detailed Description of the <RTIgt; </ RTI> <RTIgt; </ RTI> </ RTI> </ RTI> <RTIgt; The objects and advantages associated with the present invention can be readily understood by those skilled in the art. The following examples are intended to describe the present invention in further detail, but are not intended to limit the scope of the invention.

[One embodiment of charge pump circuit]

Please refer to FIG. 3, which is a circuit diagram of a charge pumping circuit according to an embodiment of the present disclosure. As shown in FIG. 3, the charge pumping circuit 1 of the embodiment of the present invention mainly includes a first voltage level generating module 10, a first voltage regulator 12, a second voltage level generating module 14, and a second voltage adjustment. 16. The first voltage level generating module 10 further includes a first capacitor C1, a second capacitor C2, and a first switch group 100. The second voltage level generating module 14 further includes a third capacitor C3 and a fourth capacitor. C4 and second switch group 140. The following is the respective electronic components in the first voltage level generating module 10 and the second voltage level generating module 14 respectively. The coupling relationship and the actuation mode are described in detail.

The first switch group 100 is configured to selectively turn on the first current path and the second current path, and the first switch group 100 includes a first switch SW1 and a second switch SW2, and the first switch SW1 and the first switch The two switch SW2s each have a switching node a (a first switching node and a third switching node), a switching node b (a second switching node and a fourth switching node), and a common node (a node not labeled) (No. A common node and a second common node). The first end and the second end of the first capacitor C1 are respectively coupled to a common node of the first switch SW1 and a common node of the second switch SW2. The first end and the second end of the second capacitor C2 are respectively coupled to the first output end_1 of the first voltage level generating module 10 and the ground potential. The switching node a of the first switching switch SW1 is coupled to the preset voltage V1 (the first preset voltage), and the switching node b of the first switching switch SW1 and the switching node a of the second switching switch SW2 are all coupled to the ground potential. The switching node b of the two switching switch SW2 is coupled between the second capacitor C2 and the first output terminal output_1.

The first voltage regulator 12 is coupled to the first switch SW1 and the second switch SW2. The first voltage regulator 12 is configured to simultaneously control switching of the first switching switch SW1 and the second switching switch SW2 to turn on or enable the first current path in the first voltage level generating module 10 The second current path in the quasi-production module 10 is turned on. In other words, the first voltage regulator 12 is configured to enable the first voltage level generating module 10 to turn on the first current path at a first time, or to enable the first voltage level generating module 10 to be in a second time. Turning on the second current path. In practice, the first switch SW1 and the second switch SW2 may be a gold type Oxygen half field effect transistor (MOSFET) or bipolar junction transistor (BJT), but not limited to the above.

The second switch group 140 is configured to selectively turn on the third current path and the fourth current path, and the second switch group 140 includes a third switch SW3 and a fourth switch SW4, and the third switch SW3 and The four switch SW4s each have a switching node a (a fifth switching node and a seventh switching node), a switching node b (a sixth switching node and an eighth switching node), and a common node (a node not labeled) (No. Three common nodes and a fourth common node). The first end and the second end of the third capacitor C3 are respectively coupled to a common node of the third switch SW3 and a common node of the fourth switch SW4. The first end and the second end of the fourth capacitor C4 are respectively coupled to the second output terminal output_2 of the second voltage level generating module 14 and the ground potential. The switching node a of the third switching switch SW3 is coupled to the preset voltage V1, and the switching node b of the third switching switch SW3 is coupled between the fourth capacitor C4 and the second output terminal output_2. The switching node a of the fourth switching switch SW4 is coupled to the preset voltage V _X (fourth preset voltage), and the switching node b of the fourth switching switch SW4 is coupled to the preset voltage V1.

It should be noted that the voltage level of the preset voltage V _X in the embodiment of the present invention is any voltage level lower than the voltage level of the preset voltage V1. In other words, the voltage level of the preset voltage V _X may be Any one of the positive voltage level, the ground potential or any one of the negative voltage levels less than the preset voltage V1 is not limited herein.

The second voltage regulator 16 is coupled to the third switch SW3 and the fourth switch SW4. The second voltage regulator 16 is configured to simultaneously control switching of the third switching switch SW3 and the fourth switching switch SW4 to turn on or enable the third current path in the second voltage level generating module 14 The fourth current path in the quasi-production module 14 is turned on. In other words, the second voltage regulator 16 is configured to enable the second voltage level generating module 14 to turn on the third current path at a third time, or to enable the second voltage level generating module 14 to be at the fourth time. The fourth current path is turned on. In practice, the third switch SW3 and the fourth switch SW4 may be a metal oxide half field effect transistor or a bipolar transistor, but not limited to the above. In one of the embodiments, the third time will continue after the second time.

In order to more clearly explain the detailed operation of the first voltage level generating module 10 to turn on the first current path and the second current path, and the details of the second voltage regulator 16 to turn on the third current path and the fourth current path. Operational situation. Please refer to FIG. 4A, FIG. 4B, FIG. 4C and FIG. 4D. FIG. 4A is a schematic diagram of the circuit operation mode when the charge pump circuit according to FIG. 3 is turned on the first current path; FIG. 4B is a diagram FIG. 4C is a schematic diagram of a circuit operation mode when the charge pump circuit according to FIG. 3 is turned on the second current path; FIG. 4C is a schematic diagram of a circuit operation mode when the charge pump circuit according to FIG. 3 is turned on the third current path; The 4D diagram is a schematic diagram of the circuit operation mode when the charge pump circuit according to FIG. 3 is turned on the fourth current path.

As shown in FIG. 4A, when the first voltage level generating module 10 is to turn on the first current path I1, the common node of the first switching switch SW1 is controlled by the first voltage regulator 12 to be coupled to the first switching. The switching node a of the switch SW1 and the common node of the second switching switch SW2 are also controlled by the first voltage regulator 12 and coupled to the switching node a of the second switching switch SW2, so that the first end of the first capacitor C1 is made The preset voltage V1 and the ground potential are respectively coupled to the second end. At this time, since the first capacitor C1 is coupled to the relationship between the preset voltage V1 and the ground potential, the preset voltage V1 starts to charge the first capacitor C1 to form the first current path I1 and the first capacitor. The voltage across _{C C1 of C1} is charged to the voltage level of the preset voltage V1. In other words, when the first current path I1 is turned on, the first capacitor C1 stores a preset voltage V1.

As shown in FIG. 4B, when the first voltage level generating module 10 is to turn on the second current path I2, the common node of the first switching switch SW1 is controlled by the first voltage regulator 12 to be coupled to the first switching. The switching node b of the switch SW1 and the common node of the second switching switch SW2 are also controlled by the first voltage regulator 12 and coupled to the switching node b of the second switching switch SW2, so that the first end of the first capacitor C1 is made And the second end is coupled to the ground potential and the first end of the second capacitor C2. At this time, since the first capacitor C1 is coupled in series to the relationship between the ground potential and the first end of the second capacitor C2, the first capacitor C1 starts to discharge the ground potential, and forms the second current path I2, and The voltage across the second capacitor C2, V _{C2 ,} is discharged to the voltage level of the reverse predetermined voltage V1. In other words, when the second current path I2 is turned on, the terminal voltage of the first terminal of the second capacitor C2 is pulled to the reverse preset voltage V1, and the first output of the first voltage level generating module 10 is caused. The voltage level output by the terminal output_1 is the reverse preset voltage V1.

As shown in FIG. 4C, when the second voltage level generating module 14 is to turn on the third current path I3, the common node of the third switching switch SW3 is controlled by the second voltage regulator 16 to be coupled to the third switching. The switching node a of the switch SW3 and the common node of the fourth switching switch SW4 are also controlled by the second voltage regulator 16 to be coupled to the switching node a of the fourth switching switch SW4, so that the first end of the third capacitor C3 is The preset voltage V1 and the preset voltage V _X are respectively coupled to the second end. At this time, since the third capacitor C3 is coupled to the relationship between the preset voltage V1 and the preset voltage V _X , the third capacitor C3 starts to be charged due to the potential difference between the preset voltage V1 and the preset voltage V _X . The third current path I3 is formed, and the voltage across the voltage V _{C3 of the} third capacitor C3 is charged to a voltage difference (a third preset voltage) between the preset voltage V1 and the preset voltage V _X . In other words, when the third current path I3 is turned on, the third capacitor C3 is charged according to the voltage difference between the preset voltage V1 and the preset voltage V _X , and the third capacitor C3 is stored with the preset voltage V1 and The voltage difference of the preset voltage V _X .

As shown in FIG. 4D, when the second voltage level generating module 14 is to turn on the fourth current path I4, the common node of the third switching switch SW3 is controlled by the second voltage regulator 16 to be coupled to the third switching. The switching node b of the switch SW3 and the common node of the fourth switching switch SW4 are also controlled by the second voltage regulator 16 and coupled to the switching node b of the fourth switching switch SW4, so that the first end of the third capacitor C3 is The first end of the fourth capacitor C4 and the preset voltage V1 are respectively coupled to the second end. At this time, because the fourth capacitor C4 is coupled in series with the relationship between the first end of the fourth capacitor C4 and the preset voltage V1, the preset voltage V1 and the cross-voltage V _C3 stored by the third capacitor _C3 (ie, preset The voltage difference between the voltage V1 and the preset voltage V _X starts to discharge the ground potential coupled to the second end of the fourth capacitor C4, and forms a fourth current path I4, so that the fourth capacitor C4 crosses The voltage V _{C4 is} equivalent to the voltage sum of the preset voltage V1 and the voltage across the voltage V _C3 stored by the third capacitor C3.

In other words, at the time of the fourth current I4 conduction path, the fourth capacitor C4 will be charged according to a preset voltage V1 and the third capacitor C3 of the voltage V _C3 across the reservoir, such that the first end of the end of the fourth capacitor C4 The voltage is pulled to the voltage of the preset voltage V1 and the voltage across the voltage V _C3 stored by the third capacitor C3, and the voltage level outputted by the second output terminal_2 of the second voltage level generating module 14 is pre- The voltage V1 is summed with the voltage across the voltage V _C3 stored by the third capacitor C3.

In practice, the charge pump circuit 1 can be placed in the display to provide a plurality of different voltage levels of the drive voltage to the display. For example, if the preset voltage V1 is a power analog voltage (for example, AVDD) supplied to the source driver, the voltage level output by the first output terminal_1 of the first voltage level generating module 10 is used. The voltage level of the second output terminal output_2 of the second voltage level generating module 14 can be a gate-off gate voltage (VGL) provided to the gate driver. It can be a high-level gate voltage (VGH) that is supplied to the gate driver.

In actual operation, the gate cutoff voltage outputted by the first output terminal output_1 of the first voltage level generating module 10 can be fed back to the second voltage level generating module 14 for receiving the preset voltage V. The node of _X is such that the preset voltage V _{X is} the gate cutoff voltage, so that the second voltage level generating module 14 can generate the gate cutoff voltage generated by the module 10 according to the first voltage level to generate the gate. Polar conduction voltage.

Please refer to FIG. 3, FIG. 4A, FIG. 4B and FIG. 5A together. FIG. 5A is a timing chart of the module according to the first voltage level of FIG. As shown in FIG. 5A, in the time interval from the time point t0 to the time point t1, the common nodes of the first switch SW1 and the second switch SW2 are not coupled to the respective switching nodes a, but are coupled to the respective Switch node b. At this time, since the voltage V _{C1 of the} first capacitor C1 is at zero potential, the ground potential is not discharged, so that the voltage V _{C2 of the} second capacitor C2 is also zero potential.

During the time interval from the time point t1 to the time point t2, the common node of the first changeover switch SW1 and the second changeover switch SW2 is coupled to the respective switching node a. At this time, the first current path I1 is turned on (as shown in FIG. 4A), and the voltage across the voltage C C1 of the first capacitor _C1 is charged to the voltage level of the preset voltage V1, and the cross of the second capacitor C2 The voltage V _{C2 is} still at zero potential.

During the time interval from the time point t2 to the time point t3, the common node of the first changeover switch SW1 and the second changeover switch SW2 is coupled to the respective switch node b. At this time, the second current path I2 is turned on (as shown in FIG. 4B), and the voltage across the voltage V _{C2 of the} second capacitor _C2 is discharged to the voltage level of the reverse preset voltage V1 (ie, -V1). . Thereby, the voltage level output by the first output terminal output_1 of the first voltage level generating module 10 is a reverse preset voltage V1 (ie, -V1).

Please refer to FIG. 3, FIG. 4C, FIG. 4D and FIG. 5B together. FIG. 5B is a timing chart of the second voltage level generating module according to FIG. It should be noted that the embodiment of FIG. 5B is configured to set the voltage to which the first end of the second capacitor C2 is pulled by the preset voltage V _X (that is, the first voltage level generating module 10). A timing chart in the case of a voltage output from the output terminal_1. As shown in FIG. 5B, in the time interval from the time point t0' to the time point t1', the common node of the third switch SW3 and the fourth switch SW4 are not coupled to the respective switching node a, but are coupled. The respective switching node b. At this time, the voltage across the third capacitor C3 and cross voltage V V _{C3 C4} of the fourth capacitor C4 are zero potential.

During the time interval from the time point t1' to the time point t2', the common node of the third changeover switch SW3 and the fourth changeover switch SW4 is coupled to the respective switching node a. At this time, the third current path I3 is turned on (as shown in FIG. 4C), and the voltage across the voltage V _{C3 of the} third capacitor _C3 is charged to a voltage difference between the preset voltage V1 and the preset voltage V _X . Wherein, since the preset voltage V _X is set to the second capacitor C2 is pulled to a voltage (i.e., -V1) of the relationship between the first end, such that the voltage across the third capacitor C3 will be equal to V _C3 twice the preset voltage V1.

The common node of the third changeover switch SW3 and the fourth changeover switch SW4 is coupled to the respective switching node b during the time interval from the time point t2' to the time point t3'. In this case, the fourth current I4 is turned path (as shown on FIG. 4D), so that the voltage V across the fourth capacitor C4 _C4 preset voltage corresponds to the voltage V1 and the third capacitor C3 stored in the _C3 cross voltage V The sum, that is, the voltage across the fourth capacitor C4, V _{C4 ,} is equal to three times the preset voltage V1. Thereby, the voltage level outputted by the second output terminal output_2 of the second voltage level generating module 14 is three times the preset voltage V1 (ie, 3V1).

In addition, if the user wants to make the second voltage level generating module 14 When the voltage level outputted by the output 2 of the output terminal is a higher voltage level, the second switch group 140 in the second voltage level generating module 14 has a large number of switching switches and a voltage withstand specification, so that the switch SW3 is switched. An electric arc effect may occur with the switch SW4 to melt the switch contacts.

[Another embodiment of the charge pump circuit]

Please refer to FIG. 6. FIG. 6 is a schematic circuit diagram of a charge pumping circuit according to another embodiment of the present disclosure. As shown in FIG. 6, the charge pumping circuit 1' of the embodiment of the present invention mainly includes a first voltage level generating module 10, a first voltage regulator 12, a second voltage level generating module 14', and a second Voltage regulator 16. Since most of the functional modules in the charge pumping circuit 1' of the present embodiment are identical to the functional modules in the charge pumping circuit 1 of the previous embodiment, the coupling of the same functional modules will not be repeated here. Relationship and action.

Different from the charge pump circuit 1 of the previous embodiment, the second voltage level generating module 14' in the charge pumping circuit 1' of the embodiment includes a third capacitor C3, a fourth capacitor C4, and a A diode D1, a second diode D2, and a second switch group 140', wherein the second switch group 140' is the third switch SW3'. In other words, the second switch group 140' has one switching node a, one switching node b, and one common node (nodes not labeled). Thereby, the second voltage level generating module 14' in the charge pumping circuit 1' of the present embodiment is lower than the second voltage level generating module 14 in the charge pumping circuit 1 of the previous embodiment. The probability of an arc effect.

The switching node a of the second switch group 140' is coupled to the preset voltage V1, the switching node b of the second switch group 140' is coupled to the preset voltage V _X ', and the common node of the second switch group 140' is coupled to the third capacitor. The second end of C3. The anode of the first diode D1 is coupled between the preset voltage V1 and the switching node a of the second switch group 140'. The cathode of the first diode D1 is coupled to the first end of the third capacitor C3. Between the anodes of the diode D2. The anode of the second diode D2 is coupled between the first end of the third capacitor C3 and the cathode of the first diode D1, and the cathode of the second diode D2 is coupled to the fourth capacitor C4 and the second output. Between end output_2. The first end of the fourth capacitor C4 is coupled between the cathode of the second diode D2 and the second output terminal_2, and the second end of the fourth capacitor C4 is coupled to the ground potential. In this embodiment, the voltage level of the preset voltage V _X ' may be the voltage level or the ground potential output by the first output terminal output_1 of the first voltage level generating module 10, but not limited thereto. .

The second switch group 140' is configured to selectively switch the third current path and the fourth current path. When the second voltage level generating module 14 ′ is to conduct the third current path, the common node of the second switch group 140 ′ is controlled by the second voltage regulator 16 and coupled to the switching node of the second switch group 140 ′. a, according to the third voltage path of the first diode D1, the second diode D2 and the fourth capacitor C4 sequentially formed by the preset voltage V1. At this time, the fourth capacitor C4 is charged due to the preset voltage V1, and the terminal voltage of the first terminal of the fourth capacitor C4 is pulled to the preset voltage V1.

When the second voltage level generating module 14 ′ is to turn on the fourth current path, the common node of the second switch group 140 ′ is controlled by the second voltage regulator 16 and coupled to the switching node of the second switch group 140 ′. b, so that the second end of the third capacitor C3 is coupled to the preset voltage V _X '. At this time, the voltage across the third capacitor C3 is equivalent to the voltage difference between the preset voltage V1 and the preset voltage V _X '. Therefore, when the common node of the second switch group 140' is coupled to the switching node a of the second switch group 140', the voltage across the fourth capacitor C4 is equivalent to the span of the preset voltage V1 and the third capacitor C3. The voltage sum of the voltages is such that the voltage level outputted by the second output terminal output_2 of the second voltage level generating module 14' is twice the voltage difference between the preset voltage V1 and the preset voltage V _X ' value.

For example, if the preset voltage V _X ' is the ground potential, the voltage level outputted by the second output terminal output_2 of the second voltage level generating module 14' will be twice the preset voltage V1; The preset voltage V _X 'is the voltage level outputted by the first output terminal output_1 of the first voltage level generating module 10, and the second voltage level generating module 14' outputs the second output terminal output_2 The voltage level will be three times the preset voltage V1.

[Possible effects of the examples]

In summary, the embodiment of the present invention provides a charge pumping circuit that transmits a first switch group in a first voltage level generating module and a second switch in a second voltage level generating module. The group selectively turns on different current paths and generates a first output terminal and a second voltage level in the first voltage level generating module by charging and discharging characteristics of a plurality of capacitors in different current paths The second output of the module can output two voltages of different voltage levels respectively. In addition, the second voltage level generating module can further generate a corresponding output voltage according to the voltage output by the first output end of the module according to the first voltage level. Thereby, the charge pumping circuit of the embodiment of the invention can be applied to the display to provide two for the display. a different gate voltage and gate turn-on voltage of different voltage levels, and only need to set a set of charge pump in the voltage level generating module for outputting the gate turn-on voltage, which reduces manufacturing cost and is very practical. Sex.

Although the present invention has been disclosed above in the above embodiments, it is not intended to limit the invention. It is within the scope of the invention to be modified and modified without departing from the spirit and scope of the invention. Please refer to the attached patent application for the scope of protection defined by the present invention.

1‧‧‧Charge pump circuit

10‧‧‧First voltage level generation module

100‧‧‧First switch group

12‧‧‧First voltage regulator

14‧‧‧Second voltage level generation module

140‧‧‧Second switch group

16‧‧‧Second voltage regulator

V1, V _X ‧‧‧Preset voltage

C1~C4‧‧‧ capacitor

SW1~SW4‧‧‧Toggle switch

a, b‧‧‧ switching node

Output_1‧‧‧first output

Output_2‧‧‧second output

Claims (12)

A charge pumping circuit includes: a first voltage level generating module having a first output, the first voltage level generating module comprising: a first capacitor; a second capacitor, the second capacitor One end is coupled to the first output end; and a first switch group is configured to selectively switch between a first current path and a second current path. When the first current path is turned on, the first capacitor is stored. The first capacitor is coupled in series with one end of the second capacitor, and the terminal voltage of the second capacitor is pulled to a second preset voltage; and a second voltage level generating module having a second output terminal, the second voltage level generating module comprising: a third capacitor; a fourth capacitor, one end of the fourth capacitor coupled to the second output And a second switch group for selectively switching between a third current path and a fourth current path. When the third current path is turned on, the third capacitor stores a third preset voltage. The third preset voltage is the first pre-pre The voltage difference between the voltage and a fourth predetermined voltage, to the fourth current path when turned on, the third capacitor coupled in series with one end of the fourth capacitor, the fourth The terminal voltage of the terminal of the capacitor is pulled to the sum of the voltages of the first predetermined voltage and the third predetermined voltage. The charge pump circuit of claim 1, wherein the second predetermined voltage is the first predetermined voltage that is opposite, the fourth predetermined voltage is the second predetermined voltage, and the second current is When the path is turned on, the voltage level output by the first output terminal is reversed by the first preset voltage, and when the fourth current path is turned on, the voltage level output by the second output terminal is three times The first preset voltage. The charge pump circuit of claim 1, wherein the first switch group further comprises: a first switch, having a first switch node, a second switch node, and a first common node, the first switch The node is coupled to the first predetermined voltage, the second switching node is coupled to a ground potential, the first common node is coupled to one end of the first capacitor, and the second switching switch has a third switching node, a fourth switching node and a second common node, the third switching node is coupled to the second switching node, the fourth switching node is coupled between the second capacitor and the first output end, the second common The node is coupled to the other end of the first capacitor; wherein, when the first current path is turned on, the first common node is coupled to the first switching node, and the second common node is coupled to the third switching node, where The first capacitor is coupled to the second capacitor, and the second common node is coupled to the second switching node, and the second common node is coupled to the fourth switching node, the first Capacitor into the ground potential The row is discharged such that the second predetermined voltage of the second capacitor is the first predetermined voltage that is inverted. The charge pumping circuit of claim 3, wherein the first voltage level generating module further comprises a first voltage regulator, the first voltage regulator being coupled to the first switching switch and the second switching switch The first voltage regulator is configured to simultaneously control switching of the first switching switch and the second switching switch to turn on the first current path or the second current path. The charge pump circuit of claim 1, wherein the second switch group further comprises: a third switch, having a fifth switch node, a sixth switch node, and a third common node, the fifth switch The node is coupled to the first preset voltage, the sixth switching node is coupled between the fourth capacitor and the second output end, the third common node is coupled to one end of the third capacitor, and a fourth switch The switch has a seventh switching node, an eighth switching node, and a fourth common node, the seventh switching node is coupled to the fourth preset voltage, and the eighth switching node is coupled to the first preset voltage, where The fourth common node is coupled to the other end of the third capacitor; wherein, when the third current path is turned on, the third common node is coupled to the fifth switching node, and the fourth common node is coupled to the seventh switching node The third capacitor is charged according to the third preset voltage. When the fourth current path is turned on, the third common node is coupled to the sixth switching node, and the fourth common node is coupled to the eighth switching node. The fourth capacitor is based on the first The preset voltage is charged with the third predetermined voltage. The charge pumping circuit of claim 5, wherein the second voltage level generating module further comprises a second voltage regulator, the second voltage regulator being coupled to the third cut The switch and the fourth switch are configured to simultaneously control switching of the third switch and the fourth switch to turn on the third current path or the fourth current path. A charge pumping circuit includes: a first voltage level generating module having a first output, the first voltage level generating module comprising: a first capacitor; a second capacitor, the second capacitor One end is coupled to the first output end; and a first switch group is configured to selectively switch between a first current path and a second current path. When the first current path is turned on, the first capacitor is stored. The first capacitor is coupled in series with one end of the second capacitor, and the terminal voltage of the second capacitor is pulled to a second preset voltage; and a second voltage level generating module has a second output end, the second voltage level generating module includes: a third capacitor; a first diode, the anode of the first diode is coupled The first predetermined voltage, the cathode of the first diode is coupled to the first end of the third capacitor; a second diode, the anode of the second diode is coupled between the first end of the third capacitor and the cathode of the first diode, and the cathode of the second diode is coupled to the second a second capacitor coupled between the cathode of the second diode and the second output; and a second switch group for selectively switching a third current path and a a fourth current path, when the third current path is turned on, a terminal voltage of the terminal of the fourth capacitor is pulled to the first preset voltage and a turn-on voltage of the first diode and the second diode a difference between the turn-on voltages, when the fourth current path is turned on, the second end of the third capacitor is coupled to a third predetermined voltage, so that the voltage level output by the second output terminal is twice a voltage difference between a predetermined voltage and a difference between the third predetermined voltage, a turn-on voltage of the first diode, and a turn-on voltage of the second diode. The charge pump circuit of claim 7, wherein the second predetermined voltage is the first predetermined voltage that is opposite, the third predetermined voltage is the second predetermined voltage, and the second current path is When the current is turned on, the voltage level outputted by the first output terminal is the first preset voltage that is reversed. When the fourth current path is turned on, the voltage across the third capacitor is the first preset voltage and the The voltage difference of the third preset voltage. The charge pump circuit of claim 7, wherein the first switch group further comprises: a first switch having a first switch node and a second switch And a first common node, the first switching node is coupled to the first predetermined voltage, the second switching node is coupled to a ground potential, the first common node is coupled to one end of the first capacitor; The second switching switch has a third switching node, a fourth switching node, and a second common node, the third switching node is coupled to the second switching node, and the fourth switching node is coupled to the second capacitor and The second common node is coupled to the other end of the first capacitor; wherein, when the first current path is turned on, the first common node is coupled to the first switching node and the second The first node is coupled to the third switching node, and the first predetermined voltage is used to charge the first capacitor. When the second current path is turned on, the first common node is coupled to the second switching node and the second common node The node is coupled to the fourth switching node, and the first capacitor discharges the ground potential such that the second predetermined voltage of the second capacitor is the first predetermined voltage that is reversed. The charge pump circuit of claim 9, wherein the first voltage level generating module further comprises a first voltage regulator, the first voltage regulator being coupled to the first switch and the second switch The first voltage regulator is configured to simultaneously control switching of the first switching switch and the second switching switch to turn on the first current path or the second current path. The charge pumping circuit of claim 7, wherein the second switch group has a fifth switching node, a sixth switching node, and a third common node, the fifth switching node being coupled to the first preset Between the voltage and the anode of the first transistor, the first The sixth switching node is coupled to the third preset voltage, and the third common node is coupled to the second end of the third capacitor. The charge pump circuit of claim 11, wherein the second voltage level generating module further comprises a second voltage regulator, the second voltage regulator is coupled to the third switch, the second voltage adjustment The controller is configured to control switching of the third switching switch to turn on the third current path or the fourth current path.