CN116232022A - Driving circuit of power switch tube and electronic equipment - Google Patents
Driving circuit of power switch tube and electronic equipment Download PDFInfo
- Publication number
- CN116232022A CN116232022A CN202310329139.XA CN202310329139A CN116232022A CN 116232022 A CN116232022 A CN 116232022A CN 202310329139 A CN202310329139 A CN 202310329139A CN 116232022 A CN116232022 A CN 116232022A
- Authority
- CN
- China
- Prior art keywords
- circuit
- effect transistor
- field effect
- current
- electrode
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 239000003990 capacitor Substances 0.000 claims abstract description 115
- 230000001105 regulatory effect Effects 0.000 claims abstract description 23
- 230000005669 field effect Effects 0.000 claims description 83
- 230000001276 controlling effect Effects 0.000 claims description 8
- 238000007599 discharging Methods 0.000 description 8
- 238000010586 diagram Methods 0.000 description 4
- 238000000034 method Methods 0.000 description 3
- 230000000087 stabilizing effect Effects 0.000 description 2
- 230000000740 bleeding effect Effects 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000012544 monitoring process Methods 0.000 description 1
- 239000004065 semiconductor Substances 0.000 description 1
Images
Classifications
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
- H02M1/00—Details of apparatus for conversion
- H02M1/08—Circuits specially adapted for the generation of control voltages for semiconductor devices incorporated in static converters
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02B—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO BUILDINGS, e.g. HOUSING, HOUSE APPLIANCES OR RELATED END-USER APPLICATIONS
- Y02B70/00—Technologies for an efficient end-user side electric power management and consumption
- Y02B70/10—Technologies improving the efficiency by using switched-mode power supplies [SMPS], i.e. efficient power electronics conversion e.g. power factor correction or reduction of losses in power supplies or efficient standby modes
Landscapes
- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Dc-Dc Converters (AREA)
Abstract
The present disclosure relates to a driving circuit of a power switching tube and an electronic device, the driving circuit including: the mirror current source is used for generating and outputting a charging current to a second end of the capacitor circuit according to a preset reference current under the condition that the voltage drop of the capacitor circuit is smaller than or equal to a first preset target value so as to improve the voltage drop; the overvoltage regulating circuit is used for outputting a bleeder current to the first end of the capacitor circuit so as to reduce the voltage drop under the condition that the voltage drop of the capacitor circuit is larger than or equal to a first preset target value. The driving circuit of the power switch tube can further improve the reliability of the power switch tube.
Description
Technical Field
The disclosure relates to the field of power semiconductor devices, and in particular relates to a driving circuit of a power switch tube and electronic equipment.
Background
Referring to fig. 1, a conventional power switch driving device generally includes a driving circuit 1, a capacitor Cn and a current limiting resistor Rg. When the power switch tube driving device works normally, in order to maintain the voltage drop of the capacitor Cn at a preset voltage drop, the driving circuit 1 is required to output a charging current Icp to charge the capacitor Cn so as to compensate the voltage loss caused by charge leakage on the capacitor Cn, and when the voltage drop of the capacitor Cn is greater than or equal to the preset voltage drop, a discharging current is output so that the capacitor Cn releases redundant positive charges, thereby achieving the purpose of stabilizing the voltage drop of the capacitor Cn at the preset voltage drop. In the case where the capacitor Cn is in a stable state, that is, in the case where the voltage drop of the capacitor Cn is no longer changed, the magnitude of the charging current output by the driving circuit 1 is equal to the magnitude of the discharging current.
In the actual working process of the conventional power switch tube driving device, the charging current output by the driving circuit has a large amplitude change, namely, when the output end of the driving circuit (the output end of the driving circuit corresponds to the OUT end of the driving chip if the driving circuit is a driving chip) outputs a high level, the charging current output by the driving circuit can be increased, and when the output end of the driving circuit outputs a low level, the charging current output by the driving circuit can be reduced. As can be seen from the foregoing, in the case where the capacitor Cn in fig. 1 is in a stable state, the bleeder current outputted from the driving circuit fluctuates greatly with the change of the charging current Icp. However, when the discharging current has larger fluctuation, the voltage drop regulating and controlling capability of the driving circuit to the capacitor Cn is easily reduced, and the voltage at two ends of the capacitor Cn is further changed greatly, so that the reliability of the power switch tube is negatively affected.
In view of the above, the present disclosure provides a driving circuit of a power switch tube, so as to solve the problem that the power switch tube driving device in the prior art has a negative effect on the reliability of the power switch tube.
Disclosure of Invention
The disclosure provides a driving circuit of a power switch tube, which is connected with a first end of a capacitance circuit, a second end of the capacitance circuit and a first end of a current-limiting resistor; the first electrode of the power switch tube is grounded, and the second electrode of the power switch tube is connected with the second end of the current-limiting resistor; the driving circuit includes: the first end of the mirror current source is connected with the second end of the capacitor circuit, and the second end of the mirror current source is used for receiving a preset reference current and generating and outputting a charging current to the second end of the capacitor circuit according to the preset reference current under the condition that the voltage drop of the capacitor circuit is smaller than or equal to a first preset target value so as to improve the voltage drop; and the first end of the overvoltage regulating circuit is connected with the first end of the capacitor circuit, and the second end of the overvoltage regulating circuit is connected with the first end of the mirror current source and the second end of the capacitor circuit and is used for outputting a release current to the first end of the capacitor circuit so as to reduce the voltage drop under the condition that the voltage drop of the capacitor circuit is larger than or equal to a first preset target value.
In one possible embodiment, the driving circuit includes: the precharge circuit is connected with the first end of the capacitor circuit and is used for charging the capacitor circuit when the driving circuit is electrified until the voltage drop of the capacitor circuit is equal to a second preset target value; wherein the second preset target value is less than or equal to the first preset target value; and the first end of the first switch circuit is connected with the second end of the capacitor circuit, and the second end of the first switch circuit is grounded and is used for conducting when the precharge circuit charges the capacitor circuit.
In a possible implementation manner, the magnitude of the bleed current output by the overvoltage regulating circuit is equal to the magnitude of the charging current output by the mirror current source under the condition that the voltage drop of the capacitor circuit is constant.
In one possible embodiment, the mirrored current source includes: the drain electrode of the first field effect transistor is used for receiving the preset reference current and is connected with the grid electrode of the first field effect transistor, and the source electrode of the first field effect transistor is connected with the negative pressure charge pump; a second field effect transistor, the drain electrode of which is connected with the second end of the capacitance circuit, the grid electrode of which is connected with the grid electrode of the first field effect transistor, and the source electrode of which is connected with the negative-pressure charge pump; and the negative-pressure charge pump is connected with the source electrode of the first field effect transistor and the source electrode of the second field effect transistor.
In one possible embodiment, the mirrored current source includes: the drain electrode of the third field effect transistor is used for receiving the preset reference current and is connected with the grid electrode of the third field effect transistor, and the source electrode of the third field effect transistor is connected with the negative pressure charge pump; a fourth field effect transistor, the drain of which is connected with the second end of the capacitance circuit, the grid of which is grounded, and the source of which is connected with the drain of the fifth field effect transistor; a fifth field effect transistor having a drain connected to the source of the fourth field effect transistor, a gate connected to the gate of the third field effect transistor, and a source connected to the negative-pressure charge pump; and the negative-pressure charge pump is connected with the source electrode of the third field effect transistor and the source electrode of the fifth field effect transistor.
In one possible embodiment, the mirrored current source includes: a current mirror.
In one possible embodiment, the power switch tube comprises a field effect transistor, the first electrode of the power switch tube is a source electrode of the field effect transistor, and the second electrode of the power switch tube is a gate electrode of the field effect transistor.
According to another aspect of the present disclosure, there is provided an electronic device including: the driving circuit of the power switch tube is described above.
In one possible implementation, the electronic device further includes: the first end and the second end of the capacitor circuit are connected with the driving circuit; the first end of the current-limiting resistor is connected with the second ends of the driving circuit and the capacitor circuit, and the second end of the current-limiting resistor is connected with the second electrode of the power switch tube; and the first electrode of the power switch tube is grounded, and the second electrode of the power switch tube is connected with the second end of the current-limiting resistor.
In one possible implementation, the driving circuit is configured to receive a pulse signal; the pulse signals comprise a disconnection signal used for controlling the disconnection of the power switch tube and a conduction signal used for controlling the conduction of the power switch tube; the driving circuit is used for conducting connection between a preset reference voltage source and the first end of the capacitor circuit under the condition that the received pulse signal is a conducting signal; and under the condition that the received pulse signal is an off signal, the connection between the first end of the capacitor circuit and the ground wire is conducted.
According to the driving circuit of the power switch tube, the charging current can be output through the mirror current source to charge the capacitor circuit, the magnitude of the charging current and the magnitude of the discharging current are further fixed on the designated current magnitude, fluctuation of the charging current and the discharging current is reduced, fluctuation of voltage regulated by the overvoltage regulating circuit is reduced, voltage drop of the capacitor circuit is maintained at a fixed value, and reliability of the power switch tube is improved.
Other features and aspects of the present disclosure will become apparent from the following detailed description of exemplary embodiments, which proceeds with reference to the accompanying drawings.
Drawings
The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate exemplary embodiments, features and aspects of the present disclosure and together with the description, serve to explain the principles of the disclosure.
Fig. 1 is a schematic structural diagram of a power switch tube driving device in the prior art.
Fig. 2 is a schematic structural diagram of a driving circuit of a power switch tube according to an embodiment of the disclosure.
Fig. 3 is a schematic structural diagram of a driving circuit of a power switch tube according to an embodiment of the disclosure.
Fig. 4 is a schematic structural diagram of a driving circuit of a power switch tube according to an embodiment of the disclosure.
Detailed Description
Various exemplary embodiments, features and aspects of the disclosure will be described in detail below with reference to the drawings. In the drawings, like reference numbers indicate identical or functionally similar elements. Although various aspects of the embodiments are illustrated in the accompanying drawings, the drawings are not necessarily drawn to scale unless specifically indicated.
The word "exemplary" is used herein to mean "serving as an example, embodiment, or illustration. Any embodiment described herein as "exemplary" is not necessarily to be construed as preferred or advantageous over other embodiments.
In addition, numerous specific details are set forth in the following detailed description in order to provide a better understanding of the present disclosure. It will be understood by those skilled in the art that the present disclosure may be practiced without some of these specific details. In some instances, methods, means, elements, and circuits well known to those skilled in the art have not been described in detail in order not to obscure the present disclosure.
Referring to fig. 1, a conventional power switch driving device generally includes a driving circuit 1, a capacitor Cn and a current limiting resistor Rg. Wherein Q is a field effect transistor, corresponding to the power switching transistor mentioned above. The driving circuit 1 generally includes: a charge pump 11, a negative voltage regulator 12, and a precharge circuit 13. When the driving circuit 1 is powered on, the precharge circuit 13 inside the driving circuit 1 rapidly charges the capacitor Cn to make the voltage drop of the capacitor Cn equal to a preset precharge value (e.g., 2 v). After this, the driving circuit 1 enters a normal operation state, and the precharge circuit 13 is turned off. When the driving circuit 1 is in a normal working state, in order to maintain the voltage drop of the capacitor Cn at a preset voltage drop (for example: 3 v), the charge pump 11 in the driving circuit 1 is required to output a charging current Icp to charge the capacitor Cn so as to compensate the voltage loss on the capacitor Cn caused by charge leakage, and when the voltage drop of the capacitor Cn is greater than or equal to the preset voltage drop, the negative voltage stabilizing regulator 12 in the driving circuit 1 is enabled to output a discharging current to enable the capacitor Cn to release redundant positive charges, so that the voltage drop of the capacitor Cn is stabilized at the preset voltage drop. In the case where the capacitor Cn is in a steady state, that is, in the case where the voltage drop of the capacitor Cn is no longer changed, the magnitude of the charging current Icp output by the charge pump 11 is equal to the magnitude of the bleeding current output by the negative voltage regulator 12. In the conventional power switch tube driving device, the charging current Icp output by the charge pump 11 may vary greatly, that is, when the output terminal of the driving circuit 1 outputs a high level, the charging current Icp output by the charge pump 11 may become large, and when the output terminal of the driving circuit 1 outputs a low level, the charging current Icp output by the charge pump 11 may decrease. As can be seen from the foregoing, when the capacitor Cn is in a stable state, the bleed current output by the negative voltage regulator 12 fluctuates greatly according to the change in the magnitude of the charging current output by the charge pump 11. However, when there is a large fluctuation in the bleed current, there is also a certain fluctuation in the voltage regulated by the negative voltage regulator 12, so that there is a large change in the voltage across the capacitor Cn, resulting in a large change in the gate voltage of the power switch tube, which negatively affects the reliability of the power switch tube.
In view of the above, referring to fig. 2, the disclosure provides a driving circuit of a power switch tube, which can output a charging current through a mirror current source to charge a capacitor circuit, so as to fix the magnitude of the charging current and the magnitude of a discharging current on a specified current magnitude, reduce the fluctuation of the charging current and the discharging current, thereby reducing the fluctuation of the voltage regulated by an overvoltage regulating circuit, and maintaining the voltage drop of the capacitor circuit at a fixed value, so as to improve the reliability of the power switch tube.
Referring to fig. 2 to 3, the present disclosure provides a driving circuit of a power switch, wherein the driving circuit 1 is connected to a first end of a capacitor circuit 2, a second end of the capacitor circuit 2, and a first end of a current limiting resistor Rg. The first electrode of the power switch tube is grounded, and the second electrode of the power switch tube is connected with the second end of the current limiting resistor Rg.
Illustratively, the driving circuit 1 includes: a mirrored current source 14 and an overvoltage regulating circuit 15.
Illustratively, the mirror current source 14 has a first terminal connected to a second terminal of the capacitive circuit 2, and a second terminal for receiving a predetermined reference current. The first terminal of the overvoltage regulating circuit 15 is connected to the first terminal of the capacitive circuit 2, and the second terminal thereof is connected to the first terminal of the mirror current source 14 and the second terminal of the capacitive circuit 2.
Illustratively, the capacitive circuit 2 may include the capacitance Cn mentioned above.
Illustratively, the mirror current source 14 is configured to generate and output a charging current to the second terminal of the capacitive circuit according to a preset reference current when the voltage drop of the capacitive circuit 2 is less than or equal to a first preset target value (corresponding to the preset voltage drop in the foregoing description), so as to increase the voltage drop. For example: taking the first preset target value as 3v as an example, the mirror current source 14 outputs the charging current to the second end of the capacitor circuit 2 when the voltage drop of the capacitor circuit is equal to 2.5 v. The direction of the charging current is from the second end of the capacitor circuit 2 to the first end of the mirror current source 14, that is, the moving direction of the negative charge in the charging current is from the first end of the mirror current source 14 to the second end of the capacitor circuit 2. Therefore, the charging current can increase the negative charge at the second end of the capacitor circuit 2, thereby increasing the voltage difference at the two ends of the capacitor circuit 2, namely increasing the voltage drop of the capacitor circuit 2, so as to achieve the purpose of increasing the voltage drop of the capacitor circuit 2 to the first preset target value 3 v. The second end of the mirror current source 14 may be connected to the preset reference current source 16 to obtain the preset reference current. The direction of the predetermined reference current is from the predetermined reference current source 16 to the second end of the mirror current source 14. The present disclosure is not limited to a specific implementation of the preset reference current source 16.
Illustratively, the overvoltage regulating circuit 15 is configured to output the bleed current to the first terminal of the capacitive circuit 2 to reduce the voltage drop of the capacitive circuit 2 when the voltage drop is greater than or equal to a first preset target value. For example: taking the first preset target value as 3v as an example, the overvoltage regulating circuit 15 can determine the voltage drop of the capacitor circuit 2 by acquiring the voltages of the first end and the second end of the capacitor circuit 2, thereby realizing the purpose of monitoring the voltage drop of the capacitor circuit 2. In case the overvoltage regulating circuit 15 monitors that the voltage drop of the capacitive circuit 2 is greater than or equal to 3v, the overvoltage regulating circuit 15 outputs a bleed current to the first terminal of the capacitive circuit 2. The direction of the bleed current is from the first end of the capacitor circuit 2 to the first end of the overvoltage regulator circuit 15, i.e. the direction of movement of the negative charge in the bleed current is from the first end of the overvoltage regulator circuit 15 to the first end of the capacitor circuit 2. It follows that the bleed current may reduce the positive charge at the first end of the capacitive circuit 2, reducing the voltage difference across the capacitive circuit 2, i.e. reducing the voltage drop across the capacitive circuit 2. In the case where the voltage drop of the capacitor circuit 2 is equal to the first preset target value, the voltage drop of the capacitor circuit 2 may be fixed at the first preset target value 3v by making the magnitude of the bleed current output by the overvoltage regulating circuit 15 equal to the magnitude of the charging current output by the mirror current source 14. The specific structure of the overvoltage regulating circuit 15 is not limited in this application.
For example, referring to fig. 3, the power switch 3 may include the above-mentioned field effect transistor Q, the first electrode of the power switch 3 may be a source of the field effect transistor Q, and the second electrode of the power switch 3 may be a gate of the field effect transistor Q. The specific implementation of the power switch 3 is not limited in this disclosure, and may include a field effect transistor or a bipolar transistor.
In one possible embodiment, the magnitude of the bleed current output by the overvoltage regulating circuit 15 is equal to the magnitude of the charging current output by the mirror current source 14, with the voltage drop of the capacitive circuit 2 constant. For example: in the case where the voltage drop of the capacitor circuit 2 is smaller than the first preset target value, the mirror current source 14 may output a charging current I1 (current magnitude is, for example, 1A) to charge the capacitor circuit 2. In the case where the mirror current source 14 charges the voltage drop of the capacitance circuit 2 to the first preset target value, the overvoltage regulating circuit 15 outputs the relief current I2 (current magnitude is, for example, 1A). Since the magnitude of the bleed current I2 is equal to the magnitude of the charging current I1, the amount of charge released by the capacitor circuit 2 by the bleed current I2 is equal to the amount of charge supplemented by the capacitor circuit 2 by the charging current I1, in other words, the bleed current I2 is used to cancel the amount of charge charged by the charging current I1 to the capacitor circuit 2, so that the voltage drop of the capacitor circuit 2 is stabilized at the first preset target value. The implementation of the overvoltage control circuit 15 can be seen in the related art.
In one possible implementation, with continued reference to fig. 3, to reduce the circuit complexity and cost of the current mirror 14, the current mirror 14 may include: the first field effect transistor M0, the second field effect transistor M1, and the negative voltage charge pump 141.
The drain of the first field effect transistor M0 is for receiving a predetermined reference current and is connected to the gate thereof, and the source thereof is connected to the negative voltage charge pump 141. The drain of the second field effect transistor M1 is connected to the second terminal of the capacitor circuit 2, the gate thereof is connected to the gate of the first field effect transistor M0, and the source thereof is connected to the negative voltage charge pump 141. The negative-pressure charge pump 141 is connected to the source of the first field-effect transistor M0 and the source of the second field-effect transistor M1. The drain electrode of the first field effect transistor can be connected with a preset reference current source to obtain a preset reference current. The specific operation of the first field effect transistor M0 and the second field effect transistor M1 can be seen from the operation of the mirror current source circuit in the related art, and the negative voltage charge pump 141 can be used to output a voltage of-3.5 v to the source of the first field effect transistor M0 and the source of the second field effect transistor M1. The specific value of the voltage output by the negative pressure charge pump 141 may be determined according to practical situations, which is not limited in this disclosure.
Illustratively, the magnitude of the charging current output by the mirrored current source 14 is equal to K1 Iref. Wherein K1 is the ratio of the width-to-length ratio of the second field effect transistor M1 to the width-to-length ratio of the first field effect transistor M0, and Iref is the magnitude of the preset reference current.
In one possible embodiment, in the case that the pulse signal received by the driving circuit 1 is a conducting signal for controlling the power switch 3 to be turned on, the connection between the preset reference voltage source 4 and the first end of the capacitor circuit 2 is turned on, so that the voltage at the second end of the capacitor circuit 2 is equal to the difference between the voltage drops of the preset reference voltage source 4 and the capacitor circuit 2, so that the mirror current source 14 can work normally, as shown in fig. 4, the mirror current source 14 may include: a third field effect transistor M3, a fourth field effect transistor M4, and a fifth field effect transistor M5.
The drain of the third field effect transistor M3 is for receiving a predetermined reference current and is connected to the gate thereof, and the source thereof is connected to the negative voltage charge pump 141. The drain of the fourth field effect transistor M4 is connected to the second terminal of the capacitive circuit 2, the gate thereof is grounded, and the source thereof is connected to the drain of the fifth field effect transistor M5. The drain of the fifth field effect transistor M5 is connected to the source of the fourth field effect transistor M4, the gate thereof is connected to the gate of the third field effect transistor M3, and the source thereof is connected to the negative voltage charge pump 141. The negative charge pump 141 is connected to the source of the third field effect transistor M3 and the source of the fifth field effect transistor M5. The drain of the third field effect transistor M3 may be connected to the preset reference current source 16 to obtain a preset reference current. The specific operation of the third, fourth and fifth field effect transistors M3, M4 and M5 can be seen in the operation of the mirror current source circuit in the related art, and the negative voltage charge pump 141 can be used to output a voltage of-3.5 v to the source of the third field effect transistor M3 and the source of the fifth field effect transistor M5. The specific value of the voltage output by the negative pressure charge pump 141 may be determined according to practical situations, which is not limited in this disclosure.
Illustratively, the magnitude of the charging current output by the mirrored current source 14 is equal to K2 Iref. Wherein K2 is the ratio of the width-to-length ratio of the fifth field effect transistor M5 to the width-to-length ratio of the third field effect transistor M3, and Iref is the magnitude of the preset reference current. The fourth field effect transistor M4 is a high voltage tolerant field effect transistor.
According to the driving circuit of the power switch tube, the mirror current source in the driving circuit can be connected with the source electrode of the fifth field effect transistor and the second end of the capacitor circuit through the high-voltage-resistant fourth field effect transistor, the grid electrode of the fourth field effect transistor is grounded, and then the voltage of the source electrode of the fourth field effect transistor is limited on GND, so that the voltage of the drain electrode of the fifth field effect transistor is limited on the potential which does not exceed the GND, and the purpose of protecting the mirror current source to work normally is achieved.
In one possible implementation, the mirrored current source 14 comprises a current mirror.
Illustratively, to improve the accuracy of the output current of the mirror current source and the output impedance of the mirror current source, the mirror current source 14 may further include: wilson current mirror. The present disclosure is not limited to a specific implementation manner of the mirror current source 14, and it is sufficient to ensure that the fluctuation range of the charging current outputted from the driving circuit 1 is within the expected range.
In one possible embodiment, referring to fig. 3, the driving circuit 1 includes: the precharge circuit 13 and the first switch circuit 17.
Illustratively, the precharge circuit 13 is connected to a first terminal of the capacitive circuit 2. The first switch circuit 17 has a first terminal connected to the second terminal of the capacitor circuit and a second terminal connected to ground.
Illustratively, the precharge circuit 13 is configured to charge the capacitor circuit 2 upon power-up of the drive circuit 1 until the voltage drop of the capacitor circuit 2 is equal to a second preset target value (corresponding to the preset precharge value hereinabove). Wherein the second preset target value is less than or equal to the first preset target value. The first switch circuit 17 is used to turn on in the case where the precharge circuit charges the capacitance circuit. For example: at the time of powering up the driving circuit 1, the precharge circuit 13 outputs a predetermined charge current to the first terminal of the capacitor circuit 2. At this time, in order to ensure that the voltage at the second end of the capacitor circuit 2 does not make the power switch 3 conductive during the process of charging the capacitor circuit 2 by the precharge circuit 13, the first switch circuit 17 is in a conductive state, the second end of the capacitor circuit 2 is grounded, and further, the voltage at the second electrode of the power switch 3 cannot reach the voltage at which the second electrode can be conductive, so that the power switch 3 cannot be conductive. In case the voltage drop of the capacitive circuit 2 is equal to a second preset target value (e.g. 2 v), the precharge circuit 13 stops outputting the preset charge current to the first terminal of the capacitive circuit 2, and at the same time the first switch circuit 17 is in an off state, disconnecting the connection between the second terminal of the capacitive circuit 2 and the ground.
For example, the magnitude of the preset charging current may be determined according to practical situations, which is not limited herein.
The location of the first switch circuit 17 shown in fig. 3 is exemplary only and is not intended to limit the present disclosure. The present disclosure is not limited to a particular implementation of the first switch circuit 17.
According to another aspect of the present disclosure, there is also provided an electronic apparatus, including: the driving circuit of the power switch tube is described above.
In one possible implementation, the electronic device further includes: a capacitor circuit, a current limiting resistor and a power switch tube.
Illustratively, the first and second ends of the capacitive circuit are both connected to the drive circuit.
The first end of the current limiting resistor is connected with the second end of the driving circuit and the second end of the capacitance circuit, and the second end of the current limiting resistor is connected with the second electrode of the power switch tube.
The first electrode of the power switch tube is grounded, and the second electrode of the power switch tube is connected with the second end of the current limiting resistor. The third electrode of the power switching transistor may be connected to the load circuit 5 or may be connected to another circuit, which is not limited in this disclosure.
In a possible embodiment, referring to fig. 3, the driving circuit 1 is further configured to receive a pulse signal. The pulse signal includes an off signal for controlling the power switching tube 3 to be turned off and an on signal for controlling the power switching tube 3 to be turned on.
The driving circuit 1 is for example configured to switch on a connection between the preset reference voltage source 4 and the first terminal of the capacitive circuit 2 (corresponding to the output of the driving circuit mentioned above) in case the received pulse signal is an on signal, and to switch on a connection between the first terminal of the capacitive circuit 2 and the ground (corresponding to the output of the driving circuit mentioned above) in case the received pulse signal is an off signal. For example: referring to fig. 3, taking an example that the voltage of the preset reference voltage source 4 is 20v and the voltage drop of the capacitor circuit 2 is 3v, when the driving circuit 1 receives the pulse signal as the on signal, the driving circuit 1 makes the second switch circuit 18 conduct the connection between the preset reference voltage source 4 and the first end of the capacitor circuit 2, and makes the third switch circuit 19 disconnect the connection between the ground line and the first end of the capacitor circuit 2. At this time, the voltage at the first terminal of the capacitance circuit 2 is equal to 20v. Since the voltage drop of the capacitor circuit 2 is equal to 3v, the voltage at the second end of the capacitor circuit 2 (i.e. the first end of the current limiting resistor Rg) is equal to 17v, so that the voltage at the second electrode of the power switch tube 3 is equal to or higher than the voltage when the second electrode can be conducted, and the power switch tube 3 is conducted. On the contrary, when the driving circuit 1 receives the pulse signal as the off signal, the driving circuit 1 makes the third switch circuit 19 conduct the connection between the ground line and the first end of the capacitor circuit 2, and makes the second switch circuit 18 disconnect the connection between the preset reference voltage source 4 and the first end of the capacitor circuit 2, so that the voltage of the first end of the capacitor circuit 2 is equal to 0v. Since the voltage drop of the capacitor circuit 2 is equal to 3v, the voltage at the second end of the capacitor circuit 2 (i.e. the first end of the current limiting resistor Rg) is equal to-3 v, so that the voltage at the second electrode of the power switch 3 is a negative voltage, i.e. the voltage at the second electrode of the power switch 3 is equal to or lower than the voltage at which it can be turned off, so that the power switch 3 is turned off.
For example, the specific value of the voltage of the preset reference voltage source 4 may be determined according to the actual situation, which is not limited in this disclosure.
The connection between the preset reference voltage source 4 and the preset reference current source 16 and the circuits, modules and electronic components inside the driving circuit 1 shown in fig. 3 is exemplary only and is not intended to limit the present disclosure. The present disclosure is not limited to the implementation of the second switching circuit 18 and the third switching circuit 19.
The foregoing description of the embodiments of the present disclosure has been presented for purposes of illustration and description, and is not intended to be exhaustive or limited to the embodiments disclosed. Many modifications and variations will be apparent to those of ordinary skill in the art without departing from the scope and spirit of the various embodiments described. The terminology used herein was chosen in order to best explain the principles of the embodiments, the practical application, or the technical improvements in the marketplace, or to enable others of ordinary skill in the art to understand the embodiments disclosed herein.
Claims (10)
1. The driving circuit of the power switch tube is characterized in that the driving circuit is connected with a first end of a capacitor circuit, a second end of the capacitor circuit and a first end of a current-limiting resistor; the first electrode of the power switch tube is grounded, and the second electrode of the power switch tube is connected with the second end of the current-limiting resistor;
the driving circuit includes:
the first end of the mirror current source is connected with the second end of the capacitor circuit, and the second end of the mirror current source is used for receiving a preset reference current and generating and outputting a charging current to the second end of the capacitor circuit according to the preset reference current under the condition that the voltage drop of the capacitor circuit is smaller than or equal to a first preset target value so as to improve the voltage drop;
and the first end of the overvoltage regulating circuit is connected with the first end of the capacitor circuit, and the second end of the overvoltage regulating circuit is connected with the first end of the mirror current source and the second end of the capacitor circuit and is used for outputting a release current to the first end of the capacitor circuit so as to reduce the voltage drop under the condition that the voltage drop of the capacitor circuit is larger than or equal to a first preset target value.
2. The drive circuit of a power switching tube according to claim 1, wherein the drive circuit comprises:
the precharge circuit is connected with the first end of the capacitor circuit and is used for charging the capacitor circuit when the driving circuit is electrified until the voltage drop of the capacitor circuit is equal to a second preset target value; wherein the second preset target value is less than or equal to the first preset target value;
and the first end of the first switch circuit is connected with the second end of the capacitor circuit, and the second end of the first switch circuit is grounded and is used for conducting when the precharge circuit charges the capacitor circuit.
3. The driving circuit of a power switch tube according to claim 1, wherein the magnitude of the bleed current output by the overvoltage regulating circuit is equal to the magnitude of the charging current output by the mirror current source under the condition that the voltage drop of the capacitor circuit is constant.
4. The power switching tube driving circuit according to claim 1, wherein the mirror current source comprises:
the drain electrode of the first field effect transistor is used for receiving the preset reference current and is connected with the grid electrode of the first field effect transistor, and the source electrode of the first field effect transistor is connected with the negative pressure charge pump;
a second field effect transistor, the drain electrode of which is connected with the second end of the capacitance circuit, the grid electrode of which is connected with the grid electrode of the first field effect transistor, and the source electrode of which is connected with the negative-pressure charge pump;
and the negative-pressure charge pump is connected with the source electrode of the first field effect transistor and the source electrode of the second field effect transistor.
5. The power switching tube driving circuit according to claim 1, wherein the mirror current source comprises:
the drain electrode of the third field effect transistor is used for receiving the preset reference current and is connected with the grid electrode of the third field effect transistor, and the source electrode of the third field effect transistor is connected with the negative pressure charge pump;
a fourth field effect transistor, the drain of which is connected with the second end of the capacitance circuit, the grid of which is grounded, and the source of which is connected with the drain of the fifth field effect transistor;
a fifth field effect transistor having a drain connected to the source of the fourth field effect transistor, a gate connected to the gate of the third field effect transistor, and a source connected to the negative-pressure charge pump;
and the negative-pressure charge pump is connected with the source electrode of the third field effect transistor and the source electrode of the fifth field effect transistor.
6. The power switching tube driving circuit according to claim 1, wherein the mirror current source comprises: a current mirror.
7. The power switching tube driving circuit according to claim 1, wherein the power switching tube comprises a field effect transistor, a first electrode of the power switching tube is a source electrode of the field effect transistor, and a second electrode of the power switching tube is a gate electrode of the field effect transistor.
8. An electronic device, the electronic device comprising: a driving circuit of a power switching tube according to any one of claims 1 to 7.
9. The electronic device of claim 8, wherein the electronic device further comprises:
the first end and the second end of the capacitor circuit are connected with the driving circuit;
the first end of the current-limiting resistor is connected with the second ends of the driving circuit and the capacitor circuit, and the second end of the current-limiting resistor is connected with the second electrode of the power switch tube;
and the first electrode of the power switch tube is grounded, and the second electrode of the power switch tube is connected with the second end of the current-limiting resistor.
10. The electronic device of claim 9, wherein the drive circuit is configured to receive a pulse signal; the pulse signals comprise a disconnection signal used for controlling the disconnection of the power switch tube and a conduction signal used for controlling the conduction of the power switch tube;
the driving circuit is used for conducting connection between a preset reference voltage source and the first end of the capacitor circuit under the condition that the received pulse signal is a conducting signal; and under the condition that the received pulse signal is an off signal, the connection between the first end of the capacitor circuit and the ground wire is conducted.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202310329139.XA CN116232022A (en) | 2023-03-30 | 2023-03-30 | Driving circuit of power switch tube and electronic equipment |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202310329139.XA CN116232022A (en) | 2023-03-30 | 2023-03-30 | Driving circuit of power switch tube and electronic equipment |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN116232022A true CN116232022A (en) | 2023-06-06 |
Family
ID=86577012
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202310329139.XA Pending CN116232022A (en) | 2023-03-30 | 2023-03-30 | Driving circuit of power switch tube and electronic equipment |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN116232022A (en) |
-
2023
- 2023-03-30 CN CN202310329139.XA patent/CN116232022A/en active Pending
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US6509781B2 (en) | Circuit and method for controlling a dynamic, bi-directional high voltage analog switch | |
| US20130293213A1 (en) | Start-up circuit and method thereof | |
| US9118238B2 (en) | Charge pump systems with adjustable frequency control | |
| US20120013317A1 (en) | Constant voltage regulator | |
| US7358708B2 (en) | Linear voltage regulator | |
| CN101087107A (en) | Power supply circuit | |
| US20040004798A1 (en) | Inrush limiter circuit | |
| CN112019012B (en) | Power supply circuit | |
| US9627962B2 (en) | Fast blocking switch | |
| WO2011102189A1 (en) | Current limiting circuit | |
| US9059699B2 (en) | Power supply switching circuit | |
| US6400189B2 (en) | Buffer circuit | |
| US6181157B1 (en) | Resistor mirror | |
| US11869886B2 (en) | ESD protection circuit, semiconductor device, and electronic apparatus | |
| CN112713642B (en) | Power supply detection switching control circuit | |
| EP2479633A2 (en) | Voltage regulator with pre-charge circuit | |
| CN107168433B (en) | Output circuit | |
| CN116232022A (en) | Driving circuit of power switch tube and electronic equipment | |
| US8582267B2 (en) | System and method to limit in-rush current | |
| US7116537B2 (en) | Surge current prevention circuit and DC power supply | |
| CN106980336B (en) | Voltage stabilizer | |
| CN112787372B (en) | Charging equipment and charging system | |
| CN113342112B (en) | Reference voltage control device and method and electronic equipment | |
| KR100266461B1 (en) | Audio system with transient tracking dual voltage power supply | |
| US8987949B1 (en) | Linear regulator with multiple outputs and local feedback |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination |