Transistor drive circuit and power supply system using the same

Abstract

The application discloses a low-power transistor driving circuit suitable for a wide input range, which dynamically adjusts the multiple and multiplication voltage of a charge pump circuit by judging the value of a power supply voltage, so as to ensure that the transistor has sufficient driving voltage, compared with the prior art, the transistor driving circuit of the application does not have to make the charge pump circuit always work in a two-fold mode, and the embedding circuit is omitted, so that the power consumption of the system is effectively reduced, and the risk of overvoltage under high-voltage conditions can be ensured.

Description

Technical Field

[0001] This invention relates to the field of power electronics technology, and more specifically, to a transistor driving circuit and a power supply system using the same. Background Technology

[0002] In existing power systems, such as Figure 1 As shown, a voltage higher than the power supply voltage V is typically generated via a charge pump circuit. BAT The voltage is used to drive the gate of transistor M, thereby turning on transistor M. For transistor M to be effectively turned on, i.e., fully conducting, the gate-source voltage of transistor M typically needs to be higher than 5V, but the supply voltage V... BAT The operating voltage range is likely 3–40V. At lower power supply voltages... BAT Under these conditions, it is necessary to use the power supply voltage V BAT Only after the pump is doubled can the resulting drive signal generate an effective drive voltage greater than 5V to effectively turn on transistor M; however, at higher supply voltages V... BAT Under these conditions, if we continue to use the power supply voltage V BAT If the driving signal obtained after pumping up the voltage by two times is used to drive transistor M, the driving signal output by the charge pump will be too high, which may cause overvoltage of the gate source of transistor M. The system needs to configure a clamping circuit to ensure the safety of the gate source voltage of transistor M.

[0003] However, in battery-powered systems such as battery monitoring systems (BMS) and fuel gauges, power consumption is a crucial metric, therefore circuit designs must prioritize low power consumption. Figure 1 In the power system, whether it is a double charge pump or a clamping circuit configuration, power consumption will be significantly increased, and there is a risk of overvoltage under high voltage conditions. Summary of the Invention

[0004] In view of this, the present invention provides a low-power transistor driving circuit suitable for a wide input range to reduce the power consumption of the power supply system.

[0005] In a first aspect, the present invention provides a transistor driving circuit for use in a power supply system, wherein one power terminal of the transistor is connected to a voltage source, characterized in that the input terminal of the transistor driving circuit is connected to the voltage source, for adaptively boosting the power supply voltage by different factors according to the value of the power supply voltage output by the voltage source, thereby generating a corresponding driving signal to drive the transistor.

[0006] Preferably, the transistor driving circuit includes:

[0007] A voltage detection circuit is used to detect the relationship between the power supply voltage and the threshold voltage, and generate a comparison signal;

[0008] A charge pump circuit is used to select the operating mode of the charge pump circuit according to the comparison signal, so as to raise the power supply voltage by different factors to an intermediate voltage in different modes and use it as a drive signal, so that the drive signal meets the drive requirements, and the drive signal is used to drive the transistor.

[0009] Preferably, when the state of the comparison signal indicates that the power supply voltage is greater than the threshold voltage, the charge pump circuit operates in a first mode, and the pumped voltage obtained by doubling the intermediate voltage of the power supply voltage is used as the drive signal; when the state of the comparison signal indicates that the power supply voltage is less than the threshold voltage, the charge pump circuit operates in a second mode, and the pumped voltage obtained by doubling the intermediate voltage of the power supply voltage is used as the drive signal.

[0010] Preferably, the threshold voltage is close to the driving voltage that enables the transistor to be fully turned on.

[0011] Preferably, the intermediate voltage is configured as the power supply voltage.

[0012] Preferably, the intermediate voltage is configured as an regulated voltage obtained by adjusting the power supply voltage through a linear regulator.

[0013] Preferably, when the state of the comparison signal indicates that the power supply voltage is greater than the threshold voltage, the adjustment voltage is configured to be stabilized at the drive voltage; when the state of the comparison signal indicates that the power supply voltage is less than the threshold voltage, the adjustment voltage is configured to be stabilized at half of the drive voltage.

[0014] Preferably, the charge pump circuit includes:

[0015] In the first mode, the selection circuit uses the intermediate voltage output as the selection signal; in the second mode, it uses twice the intermediate voltage output as the selection signal.

[0016] The second charge pump receives the power supply voltage and the selection signal, and uses the pumped voltage obtained by raising the power supply voltage to the selection signal as the drive signal.

[0017] Preferably, the charge pump circuit further includes:

[0018] A first charge pump, operating in the second mode, receives the intermediate voltage, pumps the intermediate voltage up to twice its value, and outputs twice the intermediate voltage.

[0019] Preferably, the charge pump circuit further includes:

[0020] The first charge pump, in the first mode, is not enabled and thus stops working.

[0021] Preferably, the charge pump circuit includes two charge pumps and is configured to switch the connection mode of the two charge pumps according to the state of the comparison signal, so that the charge pump circuit operates in the first mode or the second mode.

[0022] Preferably, in the first mode, the two charge pumps are connected in parallel, and in the second mode, the two charge pumps are connected in series.

[0023] Preferably, the charge pump circuit includes:

[0024] The third charge pump, in the first mode, stores the voltage on its energy storage capacitor as the power supply voltage, and outputs the sum of the power supply voltage and the intermediate voltage as the pump boost voltage; in the second mode, stores the voltage on its energy storage capacitor as the intermediate voltage, and outputs the sum of the intermediate voltage and the intermediate voltage as the pump boost voltage.

[0025] The fourth charge pump, in the first mode, stores the voltage on its energy storage capacitor as the power supply voltage, and outputs the sum of the power supply voltage and the intermediate voltage as the pump boost voltage; in the second mode, stores the voltage on its energy storage capacitor as the power supply voltage.

[0026] A switching circuit is provided for connecting the third and fourth charge pumps in parallel in the first mode and in series in the second mode.

[0027] Preferably, one power terminal of the transistor is connected to the power supply voltage, and the other power terminal is connected to an output port of the power supply system.

[0028] In a second aspect, the present invention provides a power supply system, comprising:

[0029] Voltage source

[0030] A transistor, one of its power terminals being connected to the voltage source, and,

[0031] In the transistor driving circuit described above, the driving signal is used to drive the transistor.

[0032] The present invention aims to provide a low-power transistor driving circuit suitable for a wide input range. By judging the magnitude of the power supply voltage, the multiplier and voltage multiplication of the charge pump circuit are dynamically adjusted to ensure that the transistor has sufficient driving voltage. Compared with the prior art, the transistor driving circuit of the present invention does not require the charge pump circuit to always operate in double mode and eliminates the clamping circuit, thereby effectively reducing the power consumption of the system and ensuring that there is no risk of overvoltage under high voltage conditions. Attached Figure Description

[0033] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0034] Figure 1 This is a schematic diagram of a proportional power supply system;

[0035] Figure 2 This is a schematic diagram of a transistor driving circuit according to Embodiment 1 of the present invention;

[0036] Figure 3 This is a schematic diagram of a transistor driving circuit according to Embodiment 2 of the present invention;

[0037] Figure 4 This is a schematic diagram of the charge pump circuit in the transistor driving circuit according to Embodiment 3 of the present invention. Detailed Implementation

[0038] The present invention is described below based on embodiments, but the invention is not limited to these embodiments. In the detailed description of the invention below, certain specific details are described in detail. Those skilled in the art will fully understand the invention even without these details. To avoid obscuring the essence of the invention, well-known methods, processes, flows, elements, and circuits are not described in detail.

[0039] Furthermore, those skilled in the art should understand that the accompanying drawings provided herein are for illustrative purposes only and are not necessarily drawn to scale.

[0040] Furthermore, it should be understood that in the following description, "circuit" refers to a conductive loop consisting of at least one element or sub-circuit connected by electrical or electromagnetic connections. When an element or circuit is said to be "connected" to another element or "connected" between two nodes, it can be directly coupled or connected to another element, or there may be intermediate elements. The connection between elements can be physical, logical, or a combination thereof. Conversely, when an element is said to be "directly coupled to" or "directly connected" to another element, it means that there are no intermediate elements between them.

[0041] Unless the context explicitly requires it, the words "comprising," "including," and similar terms throughout the specification and claims should be interpreted as encompassing rather than being exclusive or exhaustive; that is, meaning "including but not limited to."

[0042] In the description of this invention, it should be understood that the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance. Furthermore, in the description of this invention, unless otherwise stated, "a plurality of" means two or more.

[0043] Figure 2 This is a schematic diagram of a transistor driving circuit according to Embodiment 1 of the present invention, as shown below. Figure 2 As shown, this transistor driving circuit is applied in a battery-powered power supply system, where one power terminal of transistor M in the power supply system is connected to the power supply voltage V. BAT The other power terminal is connected to the load terminal of the power supply system. The battery can be any type of rechargeable energy storage device, such as a lithium-ion battery.

[0044] Figure 2 The transistor driving circuit shown is used to generate a driving signal V that satisfies the driving requirements of transistor M. DRV This drives the transistor M to conduct effectively. Preferably, the transistor driving circuit includes a power supply voltage detection circuit CMP and a charge pump circuit CP.

[0045] Specifically, the power supply voltage detection circuit CMP is used to detect the power supply voltage V. BAT A comparison signal V is generated based on the relationship between the voltage and the threshold voltage. CMP For example, in one implementation, when the power supply voltage V BAT When the voltage is greater than the threshold voltage, the comparison signal V CMP It is in an effective state (e.g., 1); when the power supply voltage V BAT When the voltage is less than the threshold voltage, the comparison signal V CMP The value is invalid (e.g., 0). Of course, it is understood that in other implementations, the comparison signal V... CMP The state, and the power supply voltage VBAT The relationship between the magnitude of the threshold voltage and the voltage can also be other correspondences, that is, as long as the signal V is compared... CMP The state of the power supply voltage V can correspondingly characterize the power supply voltage V. BAT The relationship between the voltage and the threshold voltage can be determined.

[0046] Here, the threshold voltage approaches the driving voltage Vgs that enables transistor M to be fully turned on. For example, in some preferred embodiments, the threshold voltage is selected as the driving voltage Vgs that enables transistor M to be fully turned on, hereinafter referred to as the driving voltage Vgs. Optionally, transistor M is a metal-oxide-semiconductor field-effect transistor (MOSFET). However, other types of electrically controlled switching devices, such as bipolar junction transistors (BJTs) and insulated-gate transistors (IGBTs), can also be used as transistors in this embodiment.

[0047] The charge pump circuit CP is used to determine the comparator signal V. CMP Select the operating mode of the charge pump circuit CP to convert the power supply voltage V in different modes. BAT The intermediate voltage, after being increased by different factors, is used as the driving signal V. DRV To drive transistor M.

[0048] More specifically, the charge pump circuit CP compares the signal V. CMP State characterization of power supply voltage V BAT When the voltage exceeds the threshold voltage, the charge pump circuit CP operates in the first mode, converting the power supply voltage V... BAT The pump-up voltage obtained after doubling the intermediate voltage is used as the drive signal V. DRV When comparing signal V CMP State characterization of power supply voltage V BAT When the voltage is less than the threshold voltage, the charge pump circuit CP operates in the second mode, converting the power supply voltage V... BAT The pump-up voltage obtained after doubling the intermediate voltage is used as the drive signal V. DRV .

[0049] Optionally, the intermediate voltage is configured to be directly selected from the power supply voltage V. BAT .

[0050] Preferably, the intermediate voltage is configured to convert the power supply voltage V BAT The regulated voltage V obtained after adjustment by the linear regulator REG Furthermore, when comparing signal V... CMP State characterization of power supply voltage V BAT When the voltage exceeds the threshold voltage, adjust the voltage V. REG Configured to stabilize at the drive voltage Vgs; when the comparison signal V CMPState characterization of power supply voltage V BAT When the voltage is less than the threshold voltage, adjust the voltage V. REG It is configured to stabilize at half of the drive voltage Vgs.

[0051] It should be noted that, in one embodiment, the threshold voltage is configured as the driving voltage Vgs of transistor M, and the intermediate voltage is configured as the power supply voltage V BAT The regulated voltage V obtained after adjustment by the linear regulator REG When the charge pump circuit CP is operating in the first mode, due to the power supply voltage V BAT The voltage is greater than the threshold voltage, i.e., the power supply voltage V. BAT The driving voltage Vgs of transistor M is greater than that of the linear regulator, and the voltage V is adjusted accordingly based on the working principle of the linear regulator. REG It can be configured to stabilize at the drive voltage Vgs, and the charge pump circuit CP will reduce the power supply voltage Vgs. BAT After doubling the intermediate voltage, i.e., the driving voltage Vgs, the resulting pump-up voltage V BAT +Vgs serves as the driving signal V DRV One power terminal (e.g., the source) of transistor M is connected to the load terminal of the power supply system, since the voltage at the load terminal is not higher than the power supply voltage V. BAT At this time, the drive signal V DRV Connecting to the control terminal of transistor M ensures that transistor M has sufficient drive voltage; however, when the charge pump circuit CP operates in the second mode, due to the power supply voltage V... BAT The voltage is less than the threshold voltage, i.e., the power supply voltage V. BAT The driving voltage Vgs of transistor M is less than that of transistor M, and it is also based on the working principle of a linear regulator, with the power supply voltage V. BAT After adjustment by the linear regulator, the voltage cannot be stabilized at the drive voltage Vgs, so the voltage V is adjusted accordingly. REG Preferably configured to stabilize at half the drive voltage Vgs, Vgs / 2, the charge pump circuit CP will reduce the power supply voltage Vgs / 2. BAT The pump-up voltage V is obtained by doubling the intermediate voltage, which is half of the driving voltage Vgs, Vgs / 2. BAT +2*Vgs / 2, i.e., V BAT +Vgs serves as the driving signal V DRV This ensures that transistor M operates at the power supply voltage V. BAT It still has sufficient driving voltage even when the voltage is below the threshold voltage.

[0052] Therefore, this invention provides a low-power transistor driving circuit suitable for a wide input range, which determines the power supply voltage V. BATThe magnitude of the value is dynamically adjusted to control the multiplier and voltage multiplication of the charge pump circuit CP, so as to ensure that the transistor M has sufficient driving voltage. Compared with the prior art, the transistor driving circuit of the present invention does not require the charge pump circuit to always work in the double mode, and eliminates the clamping circuit, thereby effectively reducing the power consumption of the system and ensuring that there is no risk of overvoltage under high voltage conditions.

[0053] Figure 3 This is a schematic diagram of a transistor driving circuit according to Embodiment 2 of the present invention. In this embodiment, the threshold voltage is configured as the driving voltage Vgs of transistor M, and the intermediate voltage is configured to be the power supply voltage V. BAT The regulated voltage V obtained after adjustment by the linear regulator REG Let's take an example to illustrate this.

[0054] refer to Figure 3 The transistor driving circuit includes a power supply voltage detection circuit CMP, a linear regulator REG, and a charge pump circuit CP.

[0055] Specifically, the power supply voltage detection circuit CMP is used to detect the power supply voltage V of the voltage source. BAT The relationship between the magnitude of the threshold voltage and the signal is used to generate a comparison signal V. CMP Here, the threshold voltage is the driving voltage Vgs of transistor M. Therefore, preferably, the power supply voltage detection circuit CMP is configured to detect the power supply voltage Vgs when the power supply voltage Vgs is released. BAT When the voltage is greater than the driving voltage Vgs, the comparison signal V CMP It is in an effective state (e.g., 1); when the power supply voltage V BAT When the voltage is less than the driving voltage Vgs, the comparison signal V CMP It is an invalid state (e.g., 0).

[0056] The linear regulator REG is used to receive the power supply voltage V. BAT and the comparison signal V CMP , the power supply voltage V BAT Converted to a more stable regulating voltage V REG Output. When the comparison signal V CMP When in an effective state, adjust the voltage V. REG Configured as the drive voltage Vgs; when the comparison signal V CMP When in an invalid state, adjust voltage V REG It is configured to be half of the drive voltage Vgs, Vgs / 2.

[0057] The charge pump circuit CP receives the comparison signal V. CMP Power supply voltage V BAT and regulating voltage V REG And based on the comparison signal V CMPThe state of the power supply voltage V BAT Increase the regulating voltage V by different factors REG Then used as the driving signal V DRV Furthermore, the charge pump circuit CP includes a first charge pump CP1, a selection circuit MUX, and a second charge pump CP2.

[0058] Among them, the first charge pump CP1 receives the comparison signal V. CMP To determine the operating mode of the charge pump circuit CP. Specifically, in the first mode, the first charge pump CP1 is not enabled and therefore does not operate; in the second mode, the first charge pump CP1 receives the regulated voltage V. REG And will adjust the voltage V REG After doubling the pump voltage, the output voltage doubles to 2*V. REG .

[0059] The selection circuit MUX receives the comparison signal V. CMP To determine the operating mode of the charge pump circuit CP, in the first mode, the regulated voltage V output by the linear regulator REG. REG The output is used as a selection signal V SEL In the second mode, the adjustment voltage will be doubled to 2*V. REG The output is used as a selection signal V SEL .

[0060] The second charge pump CP2 receives power supply voltage V. BAT and selection signal V SEL Used to convert the power supply voltage V BAT Lift selection signal V SEL The pump boost voltage obtained later is used as the drive signal V DRV .

[0061] When the charge pump circuit CP is operating in the first mode, due to the power supply voltage V BAT The comparison signal V is greater than the driving voltage Vgs of transistor M. CMP In the effective state, the regulated voltage V output by the linear regulator REG is... REG Configured to stabilize at the drive voltage Vgs, the selection circuit MUX is based on the comparison signal V. CMP The effective state will regulate the voltage V REG The output is used as a selection signal V SEL At this time, the first charge pump CP1 is not enabled and therefore does not work, while the second charge pump CP2 converts the power supply voltage V. BAT Increase the regulating voltage V by one time REG The pump boost voltage V obtained afterward BAT +Vgs serves as the driving signal V DRV .

[0062] When the charge pump circuit CP operates in the second mode, due to the power supply voltage V BAT The comparison signal V is less than the driving voltage Vgs of transistor M. CMP In the invalid state, the regulated voltage V output by the linear regulator REG is... REG Configured to stabilize at half of the drive voltage Vgs, Vgs / 2, at which point the first charge pump CP1 is enabled and operates, receiving the regulated voltage Vgs. REG And will adjust the voltage V REG After doubling the pump voltage, the output voltage doubles to 2*V. REG The selection circuit MUX selects the signal based on the comparison signal V. CMP The invalid state will double the regulating voltage 2*V REG The output is used as a selection signal V SEL The second charge pump CP2 will convert the power supply voltage V BAT Increase the regulating voltage by 2*V REG The pump boost voltage V obtained afterward BAT +2*Vgs / 2, i.e., V BAT +Vgs serves as the driving signal V DRV .

[0063] It should also be noted that the charge pump circuit CP is not limited to Figure 3 The circuit structure shown, any other known or unknown circuit form that can achieve the above function, is within the range of options for the charge pump circuit CP.

[0064] Therefore, it can be seen that the charge pump circuit CP will regulate the voltage V in the first mode. REG The pump volume is doubled, and the voltage V is adjusted. REG The preferred value is the driving voltage Vgs of transistor M; the charge pump circuit CP will regulate the voltage Vgs in the second mode. REG The pump volume is doubled, and the voltage V is adjusted. REG The preferred value is half of the driving voltage Vgs of transistor M, Vgs / 2. Ultimately, the power supply voltage is raised to the driving voltage Vgs as the driving signal to satisfy the requirement that transistor M operates at a power supply voltage Vgs. BAT It has sufficient driving voltage in different ranges.

[0065] Therefore, this invention provides a low-power transistor driving circuit suitable for a wide input range, which determines the power supply voltage V. BAT The magnitude of the value is dynamically adjusted to control the multiplier and voltage multiplication of the charge pump circuit CP, so as to ensure that the transistor M has sufficient driving voltage. Compared with the prior art, the transistor driving circuit of the present invention does not require the charge pump circuit to always work in the double mode, and eliminates the clamping circuit, thereby effectively reducing the power consumption of the system and ensuring that there is no risk of overvoltage under high voltage conditions.

[0066] Figure 4 This is a schematic diagram of the charge pump circuit in the transistor driving circuit according to Embodiment 3 of the present invention. The only difference between this embodiment and Embodiment 2 is the structure of the charge pump circuit CP; the composition and function of other modules in the circuit are the same, and will not be described again.

[0067] refer to Figure 4 The charge pump circuit CP is an adaptive charge pump circuit. In a preferred embodiment, the charge pump circuit CP consists of a third charge pump CP3, a fourth charge pump CP4, and a switching circuit including switches S1 and S2.

[0068] The charge pump circuit CP is based on the comparison signal V. CMP The system automatically switches the connection mode of the third charge pump CP3 and the fourth charge pump CP4 according to the state, so that the charge pump circuit CP operates in either the first mode or the second mode accordingly. Specifically, in the first mode, the third charge pump CP3 and the fourth charge pump CP4 are connected in parallel to adjust the voltage V. REG The pump volume is doubled, and the voltage V is adjusted. REG The preferred value is the driving voltage Vgs of transistor M; in the second mode, the third charge pump CP3 and the fourth charge pump CP4 are connected in series to adjust the voltage Vgs. REG The pump volume is doubled, and the voltage V is adjusted. REG The preferred value is half of the driving voltage Vgs of transistor M, Vgs / 2, to satisfy the requirement that transistor M operates at a power supply voltage Vgs. BAT It has sufficient driving voltage in different ranges.

[0069] The switching circuit includes switches S1 and S2, used to connect the third charge pump CP3 and the fourth charge pump CP4 in parallel in a first mode, and in series in a second mode. Specifically, switch S1 is connected between the two output terminals of the third charge pump CP3 and the fourth charge pump CP4, and is turned on in the first mode and turned off in the second mode; switch S2 is connected between the output terminal of the third charge pump CP3 and the ground terminal of the fourth charge pump CP4, and is turned off in the first mode and turned on in the second mode.

[0070] Furthermore, the third charge pump CP3 includes switches S11, S12, S13, S14, and S15, and an energy storage capacitor CF1. Specifically, switch S11 is connected to the power supply voltage V. BAT Switch S12 is connected to the regulating voltage V REG Switch S14 is connected to ground GND, and switch S15 is connected to the regulated voltage V. REGThe pump voltage of the third charge pump CP3 is output through switch S13. The energy storage capacitor CF1 is connected between the common node of switches S12 and S13 and the common node of switches S14 and S15.

[0071] More specifically, in the first mode, during the charging phase, the third charge pump CP3 has switches S11 and S14 turned on, causing the voltage stored on the energy storage capacitor CF1 to be the power supply voltage V. BAT During the discharge boost phase, switches S13 and S15 are turned on to reduce the power supply voltage V. BAT With regulating voltage V REG The sum of these values ​​serves as the pump-up voltage output; in the second mode, during the charging phase, switches S12 and S14 are turned on, causing the voltage stored on the energy storage capacitor CF1 to be the regulated voltage V. REG During the discharge boost phase, switches S13 and S15 are turned on to adjust the voltage V. REG With regulating voltage V REG The sum of these values ​​serves as the pump-up voltage output.

[0072] The fourth charge pump CP4 includes switches S21, S22, S23, and S24, and an energy storage capacitor CF2. Specifically, switch S21 is connected to the power supply voltage V. BAT Switch S23 is connected to ground GND, and switch S24 is connected to the regulated voltage V. REG The fourth charge pump CP4 is output via switch S22, providing a pump-up voltage relative to ground GND. The energy storage capacitor CF2 is connected between the common node of switches S21 and S22, and between the common node of switches S23 and S24.

[0073] More specifically, in the first mode, during the charging phase, the fourth charge pump CP4 has switches S21 and S23 turned on, causing the voltage stored in the energy storage capacitor CF2 to be equal to the power supply voltage V. BAT During the discharge boost phase, switches S22 and S24 are turned on to reduce the power supply voltage V. BAT With regulating voltage V REG The sum of these values ​​serves as the pump-up voltage output; in the second mode, during the charging phase, switches S21 and S23 are turned on, causing the voltage stored in the energy storage capacitor CF2 to be equal to the power supply voltage V. BAT During the discharge boost phase, switch S22 is turned on. Since switch S2 in the switching circuit is in the on state in this mode, the pump boost voltage output by the third charge pump CP3 is twice the regulated voltage 2*V. REG It is connected to one end of the energy storage capacitor CF2, so at the other end of the energy storage capacitor CF2, a value equal to the power supply voltage V is generated. BAT With twice the regulating voltage 2*V REG The sum of the pump boost voltages, and use this pump boost voltage as the drive signal V.DRV Output.

[0074] It should be noted that in the first mode of the charge pump circuit CP in this embodiment, the third charge pump CP3 and the fourth charge pump CP4 are connected in parallel. The advantage of this is that both energy storage capacitors can be utilized in both modes, thereby saving the volume or area of ​​the energy storage capacitors.

[0075] Therefore, it can be seen that the charge pump circuit CP will regulate the voltage V in the first mode. REG The pump boost is doubled, and the voltage V will be adjusted in the second mode. REG The charge pump circuit CP automatically switches its operating mode via a switching circuit to double the pump power, ensuring that the transistor M operates at the required power supply voltage V. BAT It has sufficient driving voltage in different ranges.

[0076] Therefore, this invention provides a low-power transistor driving circuit suitable for a wide input range, which determines the power supply voltage V. BAT The magnitude of the value is dynamically adjusted to control the multiplier and voltage multiplication of the charge pump circuit CP, so as to ensure that the transistor M has sufficient driving voltage. Compared with the prior art, the transistor driving circuit of the present invention does not require the charge pump circuit to always work in the double mode, and eliminates the clamping circuit, thereby effectively reducing the power consumption of the system and ensuring that there is no risk of overvoltage under high voltage conditions.

[0077] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. For those skilled in the art, the present invention can be modified and varied in various ways. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principle of the present invention should be included within the scope of protection of the present invention.

Claims

1. A transistor driving circuit, applied in a power supply system, wherein one power terminal of the transistor is connected to a voltage source, characterized in that, The input terminal of the transistor driving circuit is connected to the voltage source to adaptively superimpose intermediate voltages of different multiples on the power supply voltage according to the value of the power supply voltage output by the voltage source, thereby generating a driving signal to drive the transistor to be fully turned on. The driving signal is provided to the control terminal of the transistor. The transistor driving circuit includes: A voltage detection circuit is used to detect the relationship between the power supply voltage and the threshold voltage, and generate a comparison signal; A charge pump circuit is used to select the operating mode of the charge pump circuit according to the comparison signal, so as to boost the power supply voltage by different factors to the intermediate voltage in different modes and use it as the drive signal, so that the drive signal meets the drive requirements, and the drive signal is used to drive the transistor; The state of the comparison signal represents the multiple of the intermediate voltage rise of the power supply voltage when the power supply voltage is greater than the threshold voltage, which is smaller than the multiple of the intermediate voltage rise of the power supply voltage when the power supply voltage is less than the threshold voltage.

2. The transistor driving circuit according to claim 1, characterized in that, When the state of the comparison signal indicates that the power supply voltage is greater than the threshold voltage, the charge pump circuit operates in the first mode, and the pump-up voltage obtained by doubling the intermediate voltage of the power supply voltage is used as the drive signal. When the state of the comparison signal indicates that the power supply voltage is less than the threshold voltage, the charge pump circuit operates in a second mode, using the pumped voltage obtained by boosting the power supply voltage by twice the intermediate voltage as the drive signal.

3. The transistor driving circuit according to claim 1, characterized in that, The threshold voltage is close to the driving voltage that allows the transistor to be fully turned on.

4. The transistor driving circuit according to claim 1, characterized in that, The intermediate voltage is configured as the power supply voltage.

5. The transistor driving circuit according to claim 1, characterized in that, The intermediate voltage is configured as an regulated voltage obtained by adjusting the power supply voltage through a linear regulator.

6. The transistor driving circuit according to claim 5, characterized in that, When the state of the comparison signal indicates that the power supply voltage is greater than the threshold voltage, the adjustment voltage is configured to be stabilized at the drive voltage that allows the transistor to be fully turned on; When the state of the comparison signal indicates that the power supply voltage is less than the threshold voltage, the adjustment voltage is configured to be stabilized at half of the drive voltage that allows the transistor to be fully turned on.

7. The transistor driving circuit according to claim 2, characterized in that, The charge pump circuit includes: In the first mode, the selection circuit uses the intermediate voltage output as the selection signal; in the second mode, it uses twice the intermediate voltage output as the selection signal. The second charge pump receives the power supply voltage and the selection signal, and uses the pumped voltage obtained by raising the power supply voltage to the selection signal as the drive signal.

8. The transistor driving circuit according to claim 7, characterized in that, The charge pump circuit also includes: A first charge pump, operating in the second mode, receives the intermediate voltage, pumps the intermediate voltage up to twice its value, and outputs twice the intermediate voltage.

9. The transistor driving circuit according to claim 7, characterized in that, The charge pump circuit also includes: The first charge pump, in the first mode, is not enabled and thus stops working.

10. The transistor driving circuit according to claim 2, characterized in that, The charge pump circuit includes two charge pumps and is configured to switch the connection mode of the two charge pumps according to the state of the comparison signal, so that the charge pump circuit operates in the first mode or the second mode.

11. The transistor driving circuit according to claim 10, characterized in that, In the first mode, the two charge pumps are connected in parallel; in the second mode, the two charge pumps are connected in series.

12. The transistor driving circuit according to claim 10, characterized in that, The charge pump circuit includes: The third charge pump, in the first mode, stores the voltage on its energy storage capacitor as the power supply voltage, and outputs the sum of the power supply voltage and the intermediate voltage as the pump boost voltage; in the second mode, stores the voltage on its energy storage capacitor as the intermediate voltage, and outputs the sum of the intermediate voltage and the intermediate voltage as the pump boost voltage. The fourth charge pump, in the first mode, stores the voltage on its energy storage capacitor as the power supply voltage, and outputs the sum of the power supply voltage and the intermediate voltage as the pump boost voltage; in the second mode, stores the voltage on its energy storage capacitor as the power supply voltage. A switching circuit is provided for connecting the third and fourth charge pumps in parallel in the first mode and in series in the second mode.

13. The transistor driving circuit according to claim 1, characterized in that, One power terminal of the transistor is connected to the power supply voltage, and the other power terminal is connected to an output port of the power supply system.

14. A power supply system, comprising: Voltage source A transistor, one of its power terminals being connected to the voltage source, and, The transistor driving circuit according to any one of claims 1-13, wherein the driving signal is used to drive the transistor.

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