TWI675276B - Variable bias power supply device and voltage generating circuit - Google Patents

Abstract

A voltage generating circuit includes at least three power supply terminals, a control module, and a voltage conversion module. The at least three power supply terminals are divided into a first group of power supply terminals for providing a different first supply voltage and a second group of power supply terminals for providing a different second supply voltage. The control module is used for generating a selection signal according to the expected value of the output voltage. The voltage conversion module is selectively connected to one of the first group of power supply terminals to receive the corresponding first power supply voltage according to a selection signal, and is connected to one of the second group of power supply terminals to receive the corresponding second power supply terminal. The power supply voltage, and the output voltage is generated according to the received first power supply voltage and the second power supply voltage. The achieved effect can improve the conversion efficiency and reduce the system power consumption under the premise that the adjustable range of the output voltage is unchanged.

Description

Variable bias power supply device and voltage generating circuit

The invention relates to the technical field of driving a touch display, in particular to a variable bias power supply device and a voltage generating circuit capable of changing a power source.

With the gradual maturity of touch technology and display technology, touch display panels have been widely used in various fields, especially in various mobile terminal systems.

The touch display panel usually includes a touch and display driver integration module (TDDI). After the mobile terminal system converts the power supply voltage provided by the battery into several basic voltages, the voltage generating circuit in the TDDI is used for A common voltage having a certain adjustable range is generated according to these several basic voltages, so that the common electrodes in the touch display panel can be driven by the common voltage, thereby realizing normal display and touch.

Since only a part of the adjustable range of the common voltage required by the touch display panel is usually a common range, at this time, in order to ensure that the output of the voltage generating circuit in the TDDI can meet the complete adjustable range of the common voltage, the The voltage generating circuit provides a high-amplitude positive supply voltage and a high-amplitude negative supply voltage.

Taking the smart phone system as an example, the smart phone system converts the power supply voltage provided by the mobile phone battery into a power supply voltage of ± 5.6V and 1.8V. Figure 1 shows a voltage generating circuit in a technical TDDI. The voltage generating circuit 100 includes a capacitor C0, an error amplifier OP0, and two transistors M1 and M2. The transistors M1 and M2 are connected in series at a first supply voltage and a second Between the supply voltages, the common terminal of the transistors M1 and M2 provides a common voltage Vcom. The capacitor C0 is connected between the common terminal of the transistors M1 and M2 and ground. The conduction and non-conduction of the transistors M1 and M2 are controlled by the error, respectively. Output of amplifier OP0. The negative-phase input terminal of the error amplifier OP1 receives the reference voltage Vref, and the positive-phase input terminal receives the common voltage Vcom. According to the needs of the touch display device, the voltage generating circuit 100 needs to output a common voltage Vcom of -4V to 1V, so 1.8V and -5.6V are selected as the first power supply voltage and the second power supply voltage to ensure the correctness of the common voltage Vcom. Output range. However, in the touch display device, the common range of the common voltage Vcom output to the common electrode is -2.5V to 0V. For example, when the voltage generating circuit 100 outputs a common voltage Vcom of -1V, the voltage generating circuit 100 needs to generate approximately With a current of 1 mA, the power consumed is about 5.6 mW. At this time, the conversion efficiency of the voltage generating circuit 100 is only 1 / 5.6 = 18%.

Therefore, when the required common voltage is within the common range, the conversion efficiency of the traditional voltage generating circuit is very low, resulting in a waste of power consumption. Furthermore, since the conventional voltage generation is normal when the touch display panel works normally, The circuit will work in a state of low conversion efficiency for a long time, so it will cause more waste of power consumption.

Therefore, an object of the present invention is to provide a variable bias power supply device and a voltage generating circuit thereof, which can improve the conversion efficiency of a circuit and reduce the power consumption of a system while ensuring that the adjustable range of the output voltage is unchanged.

Therefore, the variable bias power supply device of the present invention includes a battery, a voltage generating circuit, and a power supply circuit.

The battery is used to provide a power voltage.

The voltage generating circuit is suitable for providing an output voltage with an adjustable range. The voltage generating circuit includes: at least three power supply terminals. The at least three power supply terminals are divided into a first group of power terminals and a second group of power terminals. Each power supply terminal in a group of power supply terminals is used to provide a different first power supply voltage, and each power supply terminal in the second group of power supply terminals is used to provide a different second power supply voltage; a control module is used to A selection signal is generated according to the expected value of the output voltage; a voltage conversion module is selectively connected to one of the first set of power supply terminals to receive the corresponding first supply voltage according to the selection signal, and is connected to the first supply voltage; One of the second set of power supply terminals is connected to receive the corresponding second supply voltage, and generates the output voltage according to the received first supply voltage and the second supply voltage.

The power supply circuit is configured to generate the plurality of different first power supply voltages and the plurality of different second power supply voltages.

Preferably, the voltage conversion module includes: an adjustment unit that selectively receives one of the plurality of first power supply voltages and one of the plurality of second power supply voltages according to the selection signal, and functions as a control signal Converting the received first supply voltage or the received second supply voltage into the output voltage; an amplifier having an inverting input terminal, a non-inverting input terminal, an output terminal, a positive power supplying terminal, and A negative power supply terminal, the inverting input terminal receives a reference voltage set according to an expected value of the output voltage, the non-inverting input terminal receives the output voltage or a sampling voltage obtained by sampling the output voltage according to a set ratio, and the output terminal provides the A control signal, the positive power supply terminal selectively receives one of the plurality of first power supply voltages according to the selection signal, and the negative power supply terminal selectively receives one of the plurality of second power supply voltages according to the selection signal.

Preferably, the first power supply voltage provided by each power supply terminal in the first group of power supply terminals is ≧ 0, and the second power supply voltage provided by each power supply terminal in the second group power supply terminal is <0.

Preferably, the output terminal of the amplifier includes a first output terminal and a second output terminal, and the control signal includes a first control signal output from the first output terminal and a first output signal output from the second output terminal. Two control signals, the adjusting unit includes: a first adjusting unit having an output terminal, and the first adjusting unit is used for selectively electrically connecting with one of the first set of power supply terminals according to the selection signal to receive all Corresponding to the first supply voltage, the opening and closing of the first adjustment unit is controlled by the first control signal. When the first adjustment unit is turned on, the output terminal of the first adjustment unit provides a positive Phase adjustment current; a second adjustment unit having an output terminal, and the second adjustment unit is used for selectively electrically connecting with one of the second set of power supply terminals according to the selection signal to receive the corresponding second The supply voltage, the opening and closing of the second adjustment unit is controlled by the second control signal, and when the second adjustment unit is turned on, the output terminal of the second adjustment unit provides an inverting adjustment current, the normal phase adjustment The current and the inverting adjustment current act on the load to generate the output voltage.

Preferably, the first adjusting unit includes: a plurality of first transistors, each of which has a first path end, a second path end, and a control end; A path terminal is electrically connected to the power supply terminal of the first group of power terminals corresponding to the first terminal, and the plurality of second path terminals are electrically connected together as the output terminal of the first adjustment unit; a first selection switch is selected according to the selection. The signal selectively electrically connects a control terminal of one of the plurality of first transistors to a first output terminal of the amplifier.

Preferably, the first adjustment unit includes: a first transistor having a first path end, a second path end, and a control end, the control end is electrically connected to the second output end of the amplifier, and the first A first path end of the transistor is used as an output end of the first adjustment unit; a second selection switch is used to selectively connect the second path end of the first transistor to the first group of power supply according to the selection signal. One of the terminals to receive the corresponding first supply voltage.

Preferably, the first transistor is a P-type transistor.

Preferably, the second adjustment unit includes: A plurality of second transistors, each of which has a first path terminal, a second path terminal, and a control terminal, and the first path terminal of each second transistor is respectively electrically connected to the second group of power supplies The corresponding power supply terminal of the terminals, the second path terminals of the plurality of second transistors are electrically connected together as an output terminal of the second adjustment unit, and a third selection switch selectively selects according to the selection signal. A control terminal of one of the plurality of second transistors is electrically connected to the second output terminal of the amplifier.

Preferably, the second adjustment unit includes a second transistor having a first path end, a second path end, and a control end, and the control end of the second transistor is electrically connected to the second of the amplifier. An output terminal, the first path terminal of the second transistor is used as the output terminal of the second adjustment unit; a fourth selection switch, which selectively electrically connects the second path terminal of the second transistor according to the selection signal One of the power supply terminals connected to the second group is connected to receive the corresponding second power supply voltage.

Preferably, the second transistor is an N-type transistor.

Another object of the present invention is to provide a voltage generating circuit that improves the conversion efficiency of a circuit and reduces the power consumption of a system while ensuring that the adjustable range of the output voltage is unchanged.

The voltage generating circuit is suitable for providing an output voltage with an adjustable range. The voltage generating circuit includes a first group of power supply terminals, a second group of power supply terminals, and a voltage conversion module. The first set of power supply terminals is used to provide a plurality of different first power supply voltages. The second set of power supply terminals is used to provide a plurality of different second power supply voltages. Voltage conversion mode The group is electrically connected to the first group of power supply terminals and the second group of power supply terminals and receives a selection signal related to an expected value of the output voltage. The voltage conversion module selects from the plurality of first supply voltages according to the selection signal. One is a normal-phase power supply voltage, and one of the plurality of second power supply voltages is selected as a negative-phase power supply voltage according to the selection signal. The voltage conversion module determines the output voltage according to a comparison result between the output voltage and the expected value. The value of the output voltage is set between the positive-phase power supply voltage and the negative-phase power supply voltage.

Preferably, the voltage conversion module includes an amplifier and an adjustment unit. The amplifier detects the output voltage and receives a reference voltage set according to an expected value of the output voltage, and compares the reference voltage with the output voltage to generate a control signal. The adjustment unit is electrically connected to the first group of power supply terminals and the second group of power supply terminals and the amplifier, and receives the selection signal and receives the plurality of first power supply voltages from the first group of power supply terminals and power from the second group of power, respectively. The plurality of second power supply voltages at the end, and the control signal from the amplifier, the adjustment unit selects one of the plurality of first power supply voltages as the normal-phase power supply voltage according to the selection signal, and according to the selection signal from the plurality of One of the second supply voltages is selected as the negative-phase supply voltage, and the adjustment unit is configured to generate the output voltage, and adjust the size of the output voltage according to the control signal, the positive-phase supply voltage, and the negative-phase supply voltage to Set the expected value of the output voltage.

Preferably, the control signal includes a first control signal and a second control signal, the selection signal includes a first bit and a second bit, and the adjustment unit includes a first adjustment unit and a second adjustment unit. The first adjusting unit receives the plurality of first A power supply voltage, the first control signal, and a first bit of the selection signal, and one of the plurality of first power supply voltages is selected as the normal-phase power supply voltage according to the first bit of the selection signal, and according to the The first control signal and the normal-phase power supply voltage generate a normal-phase adjustment current. The second adjusting unit receives the plurality of second power supply voltages, the second control signal, and the second bit of the selection signal, and selects one of the plurality of second power supply voltages as the second bit of the selection signal as The negative-phase supply voltage generates a negative-phase adjustment current according to the second control signal and the negative-phase supply voltage. The normal-phase adjustment current and the reverse-phase adjustment current act on a load to generate the output voltage.

Preferably, the voltage conversion module further includes two multiplex switch units, the two multiplex switch units are electrically connected to the first group of power supply terminals and the second group of power supply terminals, respectively, and the two multiplex switch units respectively receive the selection. The first bit of the signal and the second bit of the selection signal. The amplifier has an inverting input terminal for receiving the reference voltage, a non-inverting input terminal for detecting the output voltage, a first output terminal for providing the first control signal, and a second terminal for providing the second control signal. An output terminal, a positive power supply terminal and a negative power supply terminal. One of the two multiplex switch units selects one from the plurality of first supply voltages to supply to the positive power supply terminal of the amplifier according to the first bit of the selection signal, and the other of the two multiplex switch units according to the selection signal The second bit selects one of the plurality of second supply voltages to supply to the negative supply terminal of the amplifier.

Preferably, the voltage generating circuit further includes a control module for generating the selection signal according to an expected value of the output voltage.

The effect of the present invention is that the supply voltage of the voltage generating circuit is selected and switched according to the expected value of the output voltage, which not only ensures the adjustable range of the output voltage of the voltage generating circuit, but also significantly improves the conversion efficiency of the voltage generating circuit and reduces the The power consumption of the system prolongs the working time of the system and realizes the power-saving design.

1000‧‧‧ Variable Bias Power Supply Unit

1100‧‧‧ Battery

1200‧‧‧Power circuit

1300‧‧‧Voltage generating circuit

1310‧‧‧Control Module

1320‧‧‧Voltage Conversion Module

1321a‧‧‧First adjustment unit

1321b‧‧‧Second adjustment unit

Cf‧‧‧Capacitor

OP1‧‧‧amplifier

OP_P‧‧‧Positive power supply

OP_N‧‧‧Negative power supply

M1‧‧‧Transistor

M2‧‧‧ Transistor

MP1‧‧‧Transistor

MP2‧‧‧Transistor

MN1‧‧‧Transistor

MN2‧‧‧Transistor

K1‧‧‧selection switch

K2‧‧‧selection switch

K3‧‧‧ select switch

K4‧‧‧selection switch

MP0‧‧‧Transistor

MN0‧‧‧Transistor

ctl1‧‧‧first control signal

ctl2‧‧‧second control signal

Vp1‧‧‧ supply voltage

Vp2‧‧‧ supply voltage

Vn1‧‧‧ supply voltage

Vn2‧‧‧ supply voltage

Vout‧‧‧Output voltage

Vcom‧‧‧ public voltage

sel‧‧‧select signal

Ip‧‧‧ normal phase adjustment current

In‧‧‧ Inverted adjustment current

sel [0] ‧‧‧Select the first bit of the signal

sel [1] ‧‧‧ the second bit of the selection signal

7‧‧‧Multi-channel switch unit

8‧‧‧Multi-channel switch unit

Other features and effects of the present invention will be clearly presented in the embodiment with reference to the drawings, wherein: FIG. 1 is a circuit diagram of a prior art voltage generating circuit; and FIG. 2 is one of the variable bias power supply devices of the present invention. A circuit diagram of the embodiment; FIG. 3 is a circuit diagram of the voltage generating circuit of the embodiment; FIG. 4 is a circuit diagram of the voltage conversion module of the embodiment; FIG. 5 is a circuit diagram of the multiplex switch unit of the embodiment; 6 is a circuit diagram of the first adjustment unit of the embodiment; FIG. 7 is another circuit diagram of the first adjustment unit of the embodiment; FIG. 8 is a circuit diagram of the second adjustment unit of the embodiment; and FIG. 9 is Another circuit diagram of the second adjustment unit of this embodiment.

Before the present invention is described in detail, it should be noted that in the following description, similar elements are represented by the same numbers.

As shown in FIG. 2, an embodiment of the variable bias power supply device 1000 of the present invention is applied to a touch display device. The variable bias power supply device 1000 includes a battery 1100, a power supply circuit 1200, and a voltage generating circuit 1300.

The power supply circuit 1200 is configured to generate a variety of power supply voltages (for example, the power supply voltage Vp1, the power supply voltage Vp2, the power supply voltage Vn1, and the power supply voltage Vn2) shown in FIG.

The voltage generating circuit 1300 is used to provide an output voltage Vout with an adjustable range, and the output voltage Vout is applied as a common voltage Vcom on each common electrode in the touch display device. The voltage generating circuit 1300 is included in, for example, TDDI. In this embodiment, the voltage generating circuit 1300 has at least three power supply terminals respectively for receiving different power supply voltages, wherein the power supply terminals include a first set of power supply terminals for providing different first power supply voltages and for providing different The second set of power supply terminals of the second supply voltage, for example, the first power supply voltage provided by each power supply terminal of the first set of power supply terminals ≧ 0 (for example, the power supply voltages Vp1 and Vp2 shown in FIG. 2), the second The second power supply voltage provided by each power supply terminal in the group power supply terminal is <0 (for example, the power supply voltages Vn1 and Vn2 shown in FIG. 2).

As shown in FIG. 3, the voltage generating circuit 1300 in this embodiment includes a control module 1310 and a voltage conversion module 1320.

The control module 1310 provides a selection signal sel according to the expected value of the output voltage. The selection signal sel is used to select one of the plurality of first power supply voltages as the normal-phase power supply voltage of the voltage conversion module 1320 and to select one of the plurality of second power supply voltages. One is the inverting supply voltage of the voltage conversion module 1320. The selection signal sel is, for example, a two-bit digital signal. The selection signal includes a first bit sel [0] and a second bit sel [1]. The first bit sel [0] of the selection signal sel is used for Select the normal-phase supply voltage of the voltage conversion module 1320 (sel [0] has logic 0 and logic 1 to select voltages 0V and 1.8V), and the second bit sel [1] of the selection signal sel is used to select the voltage conversion The inverting supply voltage of module 1320 (sel [1] has logic 0 and logic 1 to select voltages -2.8V, -5.6V).

The voltage conversion module 1320 is connected to the first group of power supply terminals to receive a first power supply voltage (e.g., the power supply voltages Vp1 and Vp2 in FIG. 3) of various amplitudes ≧ 0, and is connected to the second group of power supply terminals to receive each amplitude. A second supply voltage less than 0 (for example, Vn1 and Vn2 in FIG. 3). The voltage conversion module 1320 selects one of the first power supply voltages as the normal-phase power supply voltage according to the first bit sel [0] of the selection signal output by the control module 1310, and selects according to the second bit sel [1] of the selection signal. One of each of the second power supply voltages serves as the reverse power supply voltage. The voltage conversion module 1320 generates an output voltage Vout under the action of the normal-phase power supply voltage and the reverse-phase power supply voltage.

In this embodiment, the voltage conversion module 1320 may be a Low Dropout Regulator (LDO).

As shown in Table 1, this is a correspondence table between the expected value of the output voltage and the normal-phase power supply voltage and the reverse-phase power supply voltage of the voltage conversion module.

Referring to FIG. 2 and Table 1, the power supply voltage V0 generated by the battery 1100 in the variable bias power supply device 1000 is approximately equal to 4.2V to 3.7V. The adjustable range of the output voltage is divided into a first sub-range to a third sub-range according to the amplitude use probability of the output voltage Vout, and the amplitude of each supply voltage is determined according to the boundary value of the first to third sub-range. In a touch display device, the required adjustment range of the common voltage on the common electrode is, for example, -4V to 1V, and the commonly used amplitude range is about -2.8V to 0V. Therefore, in order to improve the conversion efficiency of the voltage generating circuit 1300 The power supply circuit 1200 generates a power supply voltage Vp1 = 0V, a power supply voltage Vp2 = + 1.8V, a power supply voltage Vn1 = -2.8V, and a power supply voltage Vn2 = -5.6V according to the power supply voltage V0. The power supply voltage Vn1 can be obtained by converting the power supply voltage Vn2. (E.g. using a charge pump). The voltage generating circuit 1300 generates the output voltage Vout whose amplitude is adjustable in the range of -4V to + 1V by using the above-mentioned four kinds of power supply voltages.

Specifically, as shown in Table 1, when the expected value of the output voltage Vout (corresponding to the common voltage) is within a first sub-range (common) of -2.8V or more and 0V or less, the voltage generating circuit 1300 selects the signal sel The power supply voltage Vp1 = 0V is used as the normal-phase power supply voltage, and the power supply voltage Vn1 = -2.8V is used as the reverse-phase power supply voltage under the action of the selection signal sel. When the expected value of the output voltage Vout is greater than or equal to -4V and less than- In the second sub-range (not commonly used) of 2.8V, the voltage generating circuit 1300 sets the supply voltage Vp1 = 0V (the minimum first supply voltage received by the first group of power supply terminals) as the positive phase under the action of the selection signal sel. Power supply voltage, with the supply voltage Vn2 = -5.6V as the inverse power supply voltage under the action of the selection signal sel; when the expected value of the output voltage Vout is within the third sub-range (not commonly used) greater than 0V and less than or equal to 1V, the voltage The generation circuit 1300 uses the supply voltage Vp2 = 1.8V as the normal-phase supply voltage under the action of the selection signal sel, and sets the supply voltage Vn1 = -2.8V under the action of the selection signal sel (the absolute value received by the second group of power supply terminals is the smallest (Second supply voltage) Supply voltage for the inverter. Because of the setting of the common voltage (VCOM) of the panel, the two VCOM voltage ranges of 0 ~ 1V and -2.5V ~ -4V are only occasionally required for system applications, but they are not often set here. If the normal-phase power supply voltage is only set to 1.8V and the reverse-phase power supply voltage is only set to -5.6V, the conversion efficiency will be very low; but if the normal-phase power supply voltage is set to less than 1V or the reverse-phase power supply voltage When it is set to more than -4V, it cannot meet the needs of all system applications. Therefore, compared with the prior art, the voltage generating circuit of the embodiment of the present invention can reduce power consumption. (For example, when the VCOM voltage is between 0 ~ -2.8V, the negative power terminal is switched from -5.6V to -2.8V, the power consumption is P = V × I, and the power consumption can be reduced by half when the load current is unchanged) Therefore, it not only ensures the output range of the output voltage Vout, but also improves the conversion efficiency of the voltage generation circuit and reduces the power consumption on the basis of the prior art.

As shown in FIG. 4, the voltage conversion module 1320 of this embodiment includes two multiplex switch units 7 to 8, an amplifier OP1, an adjustment unit 1321, and a capacitor Cf, where the capacitor Cf is connected to the output terminal of the output voltage Vout and the ground. To achieve filtering and regulation.

The amplifier OP1 is configured to generate a control signal according to a comparison result between the output voltage Vout (or a sampling voltage obtained by sampling the output voltage Vout according to a certain ratio) and a reference voltage Vref, where the reference voltage Vref is determined by an expected value of the output voltage Vout. The positive power supply terminal OP_P of the amplifier OP1 receives the normal-phase power supply voltage (one of the supply voltages Vp1 and Vp2 indicated by the first bit of the selection signal), and the negative power supply terminal OP_N of the amplifier OP1 receives the voltage conversion module 1320. Inverting supply voltage (one of the supply voltages Vn1 and Vn2 indicated by the second bit of the selection signal). The control signals include a first control signal ctl1 output by a first output terminal of the amplifier OP1 and a second control signal ctl2 output by a second output terminal. The amplifier OP1 is, for example, a class AB error operational amplifier.

As shown in FIG. 5, the positive power supply terminal OP_P of the amplifier OP1 is electrically connected to one end of the multiplex switch unit 7. The multiplex switch unit 7 controls the positive supply terminal of the amplifier OP1 under the control of the first bit sel [0] of the selection signal. OP_P and one of the first set of power supply terminals So that the positive power supply terminal of the amplifier OP1 receives the positive phase power supply voltage of the voltage conversion module 1320; the negative power supply terminal of the amplifier OP1 is connected to one end of another multiplex switch unit 8, and the multiplex switch unit 8 is in the second position of the selection signal. Under the control of the bit sel [1], the negative power supply terminal OP_N of the amplifier OP1 is turned on with one of the second group of power supply terminals, so that the negative power supply terminal of the amplifier OP1 receives the reverse power supply voltage of the voltage conversion module 1320.

The adjustment unit 1321 includes a first adjustment unit 1321a and a second adjustment unit 1321b.

The conduction and non-conduction of the first adjustment unit 1321a is controlled by the first control signal ctl2. The first adjustment unit 1321a provides a positive-phase adjustment current Ip when the first adjustment unit 1321a is turned on. Output voltage Vout greater than or equal to zero. The first adjustment unit 1321a receives the first bit sel [0] of the selection signal, selects one of the supply voltages Vp1 and Vp2 as the normal-phase supply voltage of the voltage conversion module 1320, and uses the normal-phase supply voltage to generate the normal-phase adjustment. Current Ip.

The conduction and non-conduction of the second adjustment unit 1321b is controlled by the second control signal ctl2. The second adjustment unit 1321b provides an inverting adjustment current In when the second adjustment unit 1321b is on. The inverting adjustment current In acts on the load of the voltage generating circuit 1300 to generate Output voltage Vout less than 0. The second adjustment unit 1321b accepts the second bit sel [1] of the selection signal, selects one of the supply voltages Vn1 and Vn2 as the reverse supply voltage of the voltage conversion module 1320, and uses the reverse supply voltage to generate the reverse adjustment Current In. Here is an example. Assume that the current VOUT = -3V and the reference voltage VREF (expected value) Change to -1V, as shown in Table 1: The negative-phase power supply voltage should be changed from Vn2 = -5.6V to Vn1 = -2.8V, and the positive-phase power supply voltage should remain unchanged Vp1 = 0V. Correspondingly, sel [0] remains unchanged, and sel [1] needs to be adjusted so that the negative-phase supply voltage should be changed from Vn2 = -5.6V to Vn1 = -2.8V. (sel [1] specifically changes from logic 0 to logic 1 or logic 1 to logic 0, which is not particularly limited and is determined by actual application). The circuit reduces the voltage values of the first and second control signals ctl1 and ctl2 through feedback, and finally changes Vout from -3V to -1V.

Referring to FIG. 6, the first aspect of the first adjustment unit 1321 a of FIG. 4 further includes a selection switch K1 and transistors MP1 and MP2 connected in series between the power supply voltages Vp1 and Vp2. The first end of the selection switch K1 receives the first control signal ctl1, and the two second ends of the selection switch K1 are respectively connected to the control end of the transistor MP1 and the control end of the transistor MP2. A common terminal of the transistors MP1 and MP2 is electrically connected to an output terminal of the voltage generating circuit 1300 for providing an output voltage Vout.

The selection switch K1 is controlled by the first bit sel [0] of the selection signal. For example, when the first bit sel [0] of the selection signal is at the first potential, the selection switch K1 connects the control terminal of the transistor MP1 and the amplifier OP1. The first output terminal is connected so that the transistor MP1 is turned on and off under the control of the first control signal ctl1. When the transistor MP1 is turned on, the first adjustment unit 1321a generates a normal-phase adjustment current Ip according to the power supply voltage Vp1; when When the first bit sel [0] of the selection signal is at the second potential, the selection switch K1 connects the control terminal of the transistor MP2 to the first output terminal of the amplifier OP1 so that the transistor MP2 is at The first control signal ctl1 is turned on or off. When the transistor MP2 is turned on, the first adjustment unit 1321a generates a normal-phase adjustment current Ip according to the power supply voltage Vp2.

Specifically, the transistors MP1 and MP2 are, for example, P-type metal-oxide-semiconductor half-field-effect transistors.

Referring to FIG. 7, another aspect of the first adjustment unit 1321 a of FIG. 4 is further described, including a selection switch K2 and a transistor MP0. The first terminal of the selection switch K2 is electrically connected to the first path terminal of the transistor MP0, and the two second ends of the selection switch K2 respectively receive the power supply voltages Vp1 and Vp2. The control terminal of the transistor MP0 is electrically connected to the first output terminal of the amplifier OP1 to receive the first control signal ctl1.

The selection switch K2 is controlled by the first bit sel [0] of the selection signal. For example, when the first bit sel [0] of the selection signal is at the first potential, the selection switch K2 causes the first path end of the transistor MP0 to receive. The power supply voltage Vp1, when the transistor MP0 is turned on under the control of the first control signal ctl1, the first adjustment unit 1321a generates a normal-phase adjustment current Ip according to the power supply voltage Vp1; when the first bit sel [0] of the selection signal is the first At the second potential, the selection switch K2 causes the first path end of the transistor MP0 to receive the power supply voltage Vp2. When the transistor MP0 is turned on under the control of the first control signal ctl1, the first adjustment unit 1321a generates a positive phase adjustment according to the power supply voltage Vp2 Current Ip. The transistor MPO may be a P-type transistor.

Referring to FIG. 8, a circuit diagram of the second adjustment unit in FIG. 4 is further described. The second adjusting unit 1321b includes a selection switch K3 and a supply voltage Vn1 connected in series. Transistors MN1 and MN2 between Vn2 and Vn2. The first end of the selection switch K3 receives the second control signal ctl2, and the two second ends of the selection switch K3 are respectively connected to the control terminal of the transistor MN1 and the control terminal of the transistor MN2. A common terminal of the transistors MN1 and MN2 is electrically connected to an output terminal of the voltage generating circuit 1300 for providing an output voltage Vout.

The selection switch K3 is controlled by the second bit sel [1] of the selection signal. For example, when the second bit sel [1] of the selection signal is at the first potential, the selection switch K3 connects the control terminal of the transistor MN1 and the amplifier OP1. The second output terminal is connected so that the transistor MN1 is turned on and off under the control of the second control signal ctl2. When the transistor MN1 is turned on, the second adjustment unit 1321b generates an inverting adjustment current In according to the supply voltage Vn1; when When the second bit sel [1] of the selection signal is at the second potential, the selection switch K3 connects the control terminal of the transistor MN2 to the second output terminal of the amplifier OP1 so that the transistor MN2 is under the control of the second control signal ctl2 The conduction and non-conduction are realized. When the transistor MN2 is turned on, the second adjustment unit 1321b generates an inverted adjustment current In according to the power supply voltage Vn2.

Specifically, the transistor MN1 and the transistor MN2 are, for example, N-type metal-oxide-half field effect transistors.

Referring to FIG. 9, another circuit diagram of the second adjustment unit in FIG. 4 is further described. The second adjustment unit 1321b includes a selection switch K4 and a transistor MN0. The first end of the selection switch K4 is connected to the first path end of the transistor MN0, and the selection switch K4 The two second terminals of the receiving voltage Vn1 and Vn2 respectively. The control terminal of the transistor MN0 is connected to the second output terminal of the amplifier OP1 to receive the second control signal ctl2.

The selection switch K4 is controlled by the second bit sel [1] of the selection signal. For example, when the second bit sel [1] of the selection signal is at the first potential, the selection switch K4 causes the first path end of the transistor MN0 to receive The power supply voltage Vn1, when the transistor MN0 is turned on under the control of the second control signal ctl2, the second adjustment unit 1321b generates an inverting adjustment current In according to the power supply voltage Vn1; when the second bit se1 [1] of the selection signal is the first At the second potential, the selection switch K4 causes the first path terminal of the transistor MN0 to receive the power supply voltage Vn2. When the transistor MN0 is turned on under the control of the second control signal ctl2, the second adjustment unit 1321b generates an inverse adjustment according to the power supply voltage Vn2 Current In. Specifically, the transistor MN0 is, for example, an N-type metal oxide half field effect transistor.

It should be noted that in this article, relational terms such as first and second are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply that these entities or operations There is any such actual relationship or order among them. Moreover, the terms "including", "comprising", or any other variation thereof are intended to encompass non-exclusive inclusion, such that a process, method, article, or device that includes a series of elements includes not only those elements but also those that are not explicitly listed Or other elements inherent to such a process, method, article, or device. Without further restrictions, the statement "including one "..." does not exclude the existence of other identical elements in the process, method, article or equipment including the elements.

To sum up, the voltage generating circuit and the control method of the above embodiment select and switch the power supply voltage of the voltage generating circuit according to the expected value of the output voltage. Compared with the prior art, it not only ensures that the output voltage of the voltage generating circuit can be measured. The adjustment range also significantly improves the conversion efficiency of the voltage generation circuit and reduces the system power consumption, thereby extending the system's working time and achieving the power saving design, so it can indeed achieve the purpose of cost invention.

However, the above is only an embodiment of the present invention. When the scope of implementation of the present invention cannot be limited by this, any simple equivalent changes and modifications made according to the scope of the patent application and the content of the patent specification of the present invention are still the present invention. Within the scope of the invention patent.

Claims (14)

A voltage generating circuit is suitable for providing an output voltage with an adjustable range. The voltage generating circuit includes: at least three power supply terminals. The at least three power supply terminals are divided into a first group of power supply terminals and a second group of power supply terminals. Each power supply terminal in the first group of power supply terminals is used to provide a different first power supply voltage, and each power supply terminal in the second group of power supply terminals is used to provide a different second power supply voltage; a control module To generate a selection signal according to the expected value of the output voltage; a voltage conversion module to selectively connect to one of the first set of power supply terminals to receive the corresponding first supply voltage according to the selection signal, and Connected to one of the second set of power supply terminals to receive the corresponding second supply voltage, and generate the output voltage according to the received first supply voltage and the second supply voltage, the voltage conversion module includes: An adjusting unit selectively receives one of the plurality of first power supply voltages and one of the plurality of second power supply voltages according to the selection signal, and receives the control signal under the action of a control signal. The first supply voltage or the received second supply voltage is converted into the output voltage; an amplifier having an inverting input terminal, a non-inverting input terminal, an output terminal, a positive power supplying terminal and a negative power supplying terminal, The inverting input terminal receives a reference voltage set according to an expected value of the output voltage, the non-inverting input terminal receives the output voltage, the output terminal provides the control signal, and the positive power supply terminal selectively receives the multiple signals according to the selection signal. One of the first supply voltages, which The negative power supply terminal selectively receives one of the plurality of second power supply voltages according to the selection signal. The voltage generating circuit according to claim 1, wherein the first power supply voltage provided by each power supply terminal of the first group of power supply terminals ≧ 0, and the power supply circuit provided by each power supply terminal of the second group power supply terminals The second supply voltage is <0. The voltage generating circuit according to claim 2, wherein the output terminal of the amplifier includes a first output terminal and a second output terminal, and the control signal includes a first control signal output from the first output terminal and a A second control signal output by the second output terminal, the adjustment unit includes: a first adjustment unit having an output terminal, and the first adjustment unit is configured to selectively supply power to the first group according to the selection signal One of the terminals is electrically connected to receive the corresponding first supply voltage. The opening and closing of the first adjustment unit is controlled by the first control signal. When the first adjustment unit is turned on, the The output terminal provides a normal-phase adjustment current; a second adjustment unit has an output terminal, and the second adjustment unit is used for selectively electrically connecting with one of the second set of power supply terminals according to the selection signal to receive all Corresponding to the second supply voltage, the opening and closing of the second adjustment unit is controlled by the second control signal. When the second adjustment unit is turned on, the output terminal of the second adjustment unit provides an inversion Adjust the current, The normal-phase adjustment current and the reverse-phase adjustment current act on a load to generate the output voltage. The voltage generating circuit according to claim 3, wherein the first adjustment unit includes: a plurality of first transistors, each of which has a first path terminal, a second path terminal, and a control terminal, One of the power supply terminals of the first group of power supply terminals corresponding to the first path terminal of each first transistor is electrically connected, and the plurality of second path terminals are electrically connected together as an output terminal of the first adjustment unit; A first selection switch selectively connects the control terminal of one of the plurality of first transistors to the first output terminal of the amplifier according to the selection signal. The voltage generating circuit according to claim 3, wherein the first adjustment unit includes: a first transistor having a first path terminal, a second path terminal, and a control terminal, and the control terminal is electrically connected to the amplifier A second output terminal of the first transistor as the output terminal of the first adjustment unit; a second selection switch for selectively selecting the second of the first transistor according to the selection signal The path end is electrically connected to one of the power supply ends of the first set of power supply ends to receive the corresponding first supply voltage. The voltage generating circuit according to claim 4 or 5, wherein the first transistor is a P-type transistor. The voltage generating circuit according to claim 3, wherein the second adjustment unit includes: A plurality of second transistors, each of which has a first path terminal, a second path terminal, and a control terminal, and the first path terminal of each second transistor is respectively electrically connected to the second group of power supplies The corresponding power supply terminal of the terminals, the second path terminals of the plurality of second transistors are electrically connected together as an output terminal of the second adjustment unit, and a third selection switch selectively selects according to the selection signal. A control terminal of one of the plurality of second transistors is electrically connected to the second output terminal of the amplifier. The voltage generating circuit according to claim 3, wherein the second adjustment unit includes: a second transistor having a first path terminal, a second path terminal, and a control terminal, the second transistor The control terminal is electrically connected to the second output terminal of the amplifier, and the first path terminal of the second transistor is used as the output terminal of the second adjustment unit; a fourth selection switch selectively selects the second circuit according to the selection signal. The second path end of the crystal is electrically connected to one of the second set of power supply ends to receive the corresponding second power supply voltage. The voltage generating circuit according to claim 7 or 8, wherein the second transistor is an N-type transistor. A variable bias power supply device includes: a battery for providing a power voltage; a voltage generating circuit according to any one of claims 1 to 9, the plurality of power supply terminals of the voltage generating circuit respectively Receiving the plurality of supply voltages to generate the output voltage, the plurality of supply voltages including a plurality of different first supply voltages and a plurality of different second supply voltages; and A power supply circuit is configured to generate the plurality of different first power supply voltages and the plurality of different second power supply voltages. A voltage generating circuit is suitable for providing an output voltage with an adjustable range. The voltage generating circuit includes: a first group of power supply terminals for providing a plurality of different first power supply voltages; a second group of power supply terminals for To provide a plurality of different second power supply voltages; a voltage conversion module electrically connected to the first group of power supply terminals and the second group of power supply terminals and receiving a selection signal related to an expected value of the output voltage, the voltage conversion The module selects one of the plurality of first supply voltages as a normal-phase supply voltage according to the selection signal, selects one of the plurality of second supply voltages as a negative-phase supply voltage according to the selection signal, and the voltage conversion mode The group sets the value of the output voltage between the positive-phase power supply voltage and the negative-phase power supply voltage according to a comparison result between the output voltage and the expected value. The voltage conversion module includes an amplifier that detects the output voltage and Receiving a reference voltage set according to an expected value of the output voltage, and comparing the reference voltage with the magnitude of the output voltage to generate a control signal, an adjustment Element, electrically connected to the first group and the second supply terminal and the supply terminal of the amplifier group, and receives the selection signal, and receives from the first The plurality of first power supply voltages of the group power supply terminal, the plurality of second power supply voltages from the second group power supply terminal, and the control signal from the amplifier. The adjustment unit selects from the plurality of first power supply voltages according to the selection signal. One is selected as the normal-phase power supply voltage, and one is selected as the negative-phase power supply voltage from the plurality of second power supply voltages according to the selection signal. The adjustment unit is configured to generate the output voltage, and according to the control signal, the normal-phase power supply voltage The power supply voltage and the negative-phase power supply voltage are used to adjust the size of the output voltage to meet the desired value setting of the output voltage. The voltage generating circuit according to claim 11, wherein the control signal includes a first control signal and a second control signal, the selection signal includes a first bit and a second bit, and the adjustment unit includes a The first adjusting unit receives the plurality of first power supply voltages, the first control signal, and a first bit of the selection signal, and selects one of the plurality of first power supply voltages according to the first bit of the selection signal. As the normal-phase power supply voltage and generating a normal-phase adjustment current according to the first control signal and the normal-phase power supply voltage, a second adjustment unit receives the plurality of second power supply voltages, the second control signal, and the selection. A second bit of the signal, and one of the plurality of second supply voltages is selected as the negative phase according to the second bit of the selection signal A supply voltage, and a negative-phase adjustment current is generated according to the second control signal and the negative-phase supply voltage, and the positive-phase adjustment current and the reverse-phase adjustment current act on a load to generate the output voltage. The voltage generating circuit according to claim 12, wherein the voltage conversion module further includes two multiplex switch units, and the two multiplex switch units are electrically connected to the first group of power supply terminals and the second group of power supply terminals, respectively. The two multiplex switch units respectively receive the first bit of the selection signal and the second bit of the selection signal. The amplifier has an inverting input terminal for receiving the reference voltage, and a non-inverting input for detecting the output voltage. Terminal, a first output terminal that provides the first control signal, a second output terminal that provides the second control signal, a positive power supply terminal, and a negative power supply terminal, one of the two multiplex switch units is based on the selection signal The first bit selects one of the plurality of first power supply voltages to supply to the positive power supply terminal of the amplifier, and the other of the two multiplex switch units supplies power from the plurality of second power sources according to the second bit of the selection signal. One of the voltages is selected to be supplied to the negative supply terminal of the amplifier. The voltage generating circuit according to claim 11, further comprising a control module for generating the selection signal according to an expected value of the output voltage.