CN210839350U - Power supply circuit of ammeter - Google Patents
Power supply circuit of ammeter Download PDFInfo
- Publication number
- CN210839350U CN210839350U CN201922337824.9U CN201922337824U CN210839350U CN 210839350 U CN210839350 U CN 210839350U CN 201922337824 U CN201922337824 U CN 201922337824U CN 210839350 U CN210839350 U CN 210839350U
- Authority
- CN
- China
- Prior art keywords
- signal
- unit
- output
- current
- comparator
- 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.)
- Active
Links
Images
Landscapes
- Dc-Dc Converters (AREA)
Abstract
The utility model discloses a power supply circuit of ammeter, including flyback main circuit, flyback main circuit includes switch tube S1, transformer T1, resistance Rs to and diode D1 and electric capacity C1 with the secondary winding of transformer T1 establish ties, output conduct after D1 and C1 rectification power supply circuit 'S output, resistance Rs establish ties in the return circuit of switch tube S1 and transformer primary winding, the voltage at resistance Rs both ends does switch tube S1' S current detection signal, its characterized in that: still include control circuit, control circuit includes magnetic field unit 1, current-limiting unit 2, voltage stabilization unit 3, drive generation unit 4, the utility model relates to a power supply circuit of ammeter can avoid the interference of outside strong magnetic field, simple structure, and is with low costs.
Description
Technical Field
The utility model relates to a smart electric meter's technical field, concretely relates to supply circuit of ammeter.
Background
In recent years, smart meters have been widely used. And smart electric meter has a problem, if there is the interference of strong magnetic field in smart electric meter's outside, makes the supply circuit of ammeter go wrong, and then causes smart electric meter's meter electric quantity to go wrong. Therefore, how to prevent the power supply circuit of the electric meter from being interfered is an urgent problem to be solved in the industry.
Many existing solutions are too complex and expensive to avoid being disturbed by strong external magnetic fields by means of shielding, for example by adding magnetic field shielding means around the periphery of the meter. For example, chinese patent CN204758820 compensates for the difference in the fuel gauge due to disturbance by supplementing the amount of electricity, and requires a complicated algorithm and program to solve the problem.
SUMMERY OF THE UTILITY MODEL
An object of the utility model is to provide a supply circuit of ammeter to solve the problem that proposes in the above-mentioned background art, avoid the ammeter to receive the interference of outside strong magnetic field.
In order to achieve the above object, the utility model provides a following technical scheme:
a power supply circuit of an electric meter comprises a flyback main circuit, wherein the flyback main circuit comprises a switching tube S1, a transformer T1, a resistor Rs, a diode D1 and a capacitor C1 which are connected with a secondary winding of a transformer T1 in series, the output end rectified by D1 and C1 serves as the output end of the power supply circuit, the resistor Rs is connected in series in a loop of the switching tube S1 and a primary winding of the transformer, the voltage at two ends of the resistor Rs serves as a current detection signal of the switching tube S1, and the power supply circuit further comprises a control circuit, and the control circuit comprises a magnetic field unit, a current limiting unit, a voltage stabilizing unit and a drive generating unit;
the magnetic field unit detects the intensity of a magnetic field, and when the intensity of the detected magnetic field exceeds a preset value, a compensation signal Vc is output to the current limiting unit;
the current limiting unit compares a current detection signal of the switching tube S1 with a preset current value Iref, and outputs a current limiting signal Vi to the drive generating unit when the current detection signal is greater than the preset current value Iref; when receiving the compensation signal Vc output by the magnetic field unit, controlling the value of the current limiting signal Vi to increase along with the increase of the compensation signal Vc;
the voltage stabilizing unit is used for detecting the output voltage Vo of the power supply circuit, presetting a preset voltage Vref, and outputting a feedback signal Vf to the driving generation unit, wherein the feedback signal Vf represents the difference between the output voltage Vo and the preset voltage Vref, and the voltage stabilizing unit is used for controlling the output voltage to be equal to the preset voltage Vref;
the drive generation unit receives the current limiting signal Vi and the feedback signal Vf, and generates a drive signal Vd according to the feedback signal when only the feedback signal Vf is received, so that the duty ratio of the drive signal changes according to the change of the feedback signal; when receiving the current limit signal Vi, the driving signal Vd is generated based on the current limit signal, and the duty ratio of the driving signal is controlled to increase as the current limit signal Vi increases.
Preferably, the magnetic field unit includes a hall element H, a first operational amplifier, a transistor Q1 and a resistor R1, the hall element H is powered by a constant current source, two ends of the hall element H are connected with an input end of the first operational amplifier, an output end of the first operational amplifier is connected with a base of the transistor Q1, a collector of the transistor Q1 is connected with the constant current source, an emitter of the transistor Q1 is connected with the resistor R1 in series and then grounded, a non-grounded end of the resistor R1 serves as an output end of the magnetic field unit, and a voltage across the resistor R1 is the compensation signal Vc.
Preferably, the magnetic field unit further comprises a comparing unit, the comparing unit receives a slope signal of the current of the switching tube S1, compares the slope signal with a set value, and outputs a compensation signal Vc when the slope signal is greater than the set value.
Preferably, the comparison unit further controls the amplitude of the compensation signal Vc output by the comparison unit to increase with the increase of the slope signal.
Preferably, the current limiting unit includes a first comparator and resistors R2 and R3, an inverting input terminal of the first comparator is connected to the resistor Rs and is configured to receive the current detection signal, a current preset value Iref is input to a non-inverting input terminal of the first comparator through the resistor R2, the compensation signal Vc is input to the non-inverting input terminal of the first comparator through the resistor R3, and an output terminal of the first comparator serves as an output terminal of the current limiting unit and outputs the current limiting signal Vi.
Preferably, the current limiting unit includes a second comparator, a third comparator, and resistors R9 and R10, an inverting input terminal of the second comparator is connected to the resistor Rs for receiving the current detection signal, the current preset value Iref is input to a non-inverting input terminal of the second comparator through the resistor R9, an inverting input terminal of the third comparator is connected to a small voltage Vcs with an amplitude close to zero, the compensation signal Vc is input to the non-inverting input terminal of the third comparator, an output terminal of the third comparator is connected to the non-inverting input terminal of the second comparator through the resistor R10, and an output terminal of the second comparator is used as an output terminal of the current limiting unit to output the current limiting signal Vi.
Preferably, the voltage stabilizing unit includes a second operational amplifier and a peripheral circuit, the peripheral circuit includes a capacitor C1 and resistors R4, R5 and R6, both ends of the resistors R4 and R5 are connected to both ends of the output of the power supply circuit, respectively, a common end of the resistors R4 and R5 is connected to an inverting input end of the second operational amplifier, one end of the resistor R6 is connected to the inverting input end of the second operational amplifier, the other end of the resistor R6 is connected to the output end of the second operational amplifier after being connected to the capacitor C1 in series, the non-inverting input end of the second operational amplifier inputs the preset voltage value Vref, and the output end of the second operational amplifier serves as the output end of the voltage stabilizing unit to output the feedback signal Vf.
Preferably, the drive generation unit is an SR flip-flop, a Q terminal of the SR flip-flop is used as an output terminal of the drive generation unit and is configured to output the drive signal Vd, an output terminal S is connected to a control terminal of a switching tube S1 of the flyback main circuit, an input terminal R7 is connected to an output terminal of the current limiting unit and is configured to receive the current limiting signal Vi, and an input terminal R8 is connected to an output terminal of the voltage stabilizing unit and is configured to receive the feedback signal Vf.
Preferably, the input terminal R7 has a higher priority than the input terminal R8.
The utility model provides a power supply circuit of ammeter possesses following beneficial effect: as a power supply circuit of the electric meter, the interference of an external strong magnetic field can be avoided, the structure is simple, and the cost is low.
Drawings
Fig. 1 is a schematic diagram of the circuit structure of the present invention;
fig. 2 is a schematic diagram of a circuit structure of the magnetic field unit of the present invention;
fig. 3 is a schematic circuit diagram of a current limiting unit according to a first embodiment of the present invention;
fig. 4 is a schematic circuit diagram of a current limiting unit according to a second embodiment of the present invention;
fig. 5 is a schematic diagram of a circuit structure of the voltage stabilizing unit of the present invention;
fig. 6 is a schematic diagram of a circuit structure of the drive generation unit according to the present invention;
fig. 7 is a cycle chart of the discontinuous mode of the present invention.
Detailed Description
The technical solutions in the embodiments of the present invention will be described clearly and completely with reference to the accompanying drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only some embodiments of the present invention, not all embodiments.
As shown in fig. 1, a power supply circuit of an electric meter includes a flyback main circuit, where the flyback main circuit includes a switching tube S1, a transformer T1, a resistor Rs, and a diode D1 and a capacitor C1 connected in series with a secondary winding of the transformer T1, an output end rectified by D1 and C1 is used as an output end of the power supply circuit, the resistor Rs is connected in series in a loop of the switching tube S1 and a primary winding of the transformer, a voltage at two ends of the resistor Rs is used as a current detection signal of the switching tube S1, and the power supply circuit further includes a control circuit, and the control circuit includes a magnetic field unit 1, a current limiting unit 2, a voltage stabilizing unit 3, and a drive generating unit 4;
the magnetic field unit 1 detects the intensity of a magnetic field, and when the detected intensity of the magnetic field exceeds a preset value, a compensation signal Vc is output to the current limiting unit 2;
the current limiting unit 2 compares the current detection signal of the switching tube S1 with a preset current value Iref, and outputs a current limiting signal Vi to the drive generating unit 4 when the current detection signal is greater than the preset current value Iref; and when receiving the compensation signal Vc output by the magnetic field unit 1, controlling the value of the current limiting signal Vi to increase as the compensation signal Vc increases;
the voltage stabilizing unit 3 detects an output voltage Vo of the power supply circuit, presets a preset voltage value Vref, and outputs a feedback signal Vf to the driving generating unit 4, wherein the feedback signal Vf represents a difference value between the output voltage Vo and the preset voltage value Vref, and the voltage stabilizing unit 3 is configured to control the output voltage to be equal to the preset voltage value Vref;
the drive generating unit 4 receives the current limiting signal Vi and the feedback signal Vf, and generates a drive signal Vd according to the feedback signal when only the feedback signal Vf is received, so that the duty ratio of the drive signal changes according to the change of the feedback signal; when receiving the current limit signal Vi, the driving signal Vd is generated based on the current limit signal, and the duty ratio of the driving signal is controlled to increase as the current limit signal Vi increases.
As shown in fig. 2, the magnetic field unit 1 includes a hall element H, a first operational amplifier 5, a transistor Q1 and a resistor R1, the hall element H is powered by a constant current source 6, two ends of the hall element H are connected to an input end of the first operational amplifier 5, an output end of the first operational amplifier 5 is connected to a base of the transistor Q1, a collector of the transistor Q1 is connected to the constant current source 6, an emitter is connected to the resistor R1 in series and then grounded, a non-grounded end of the resistor R1 serves as an output end of the magnetic field unit, and a voltage across the resistor R1 is the compensation signal Vc.
Further, the magnetic field unit further comprises a comparison unit, the comparison unit receives a slope signal of the current of the switching tube S1, compares the slope signal with a set value, and outputs a compensation signal Vc when the slope signal is greater than the set value.
Further, the comparison unit also controls the amplitude of the compensation signal Vc output by the comparison unit to increase with the increase of the slope signal.
As shown in fig. 3, the current limiting unit 2 includes a first comparator 7 and resistors R2 and R3, an inverting input terminal of the first comparator 7 is connected to the resistor Rs for receiving the current detection signal, a current preset value Iref is input to a non-inverting input terminal of the first comparator 7 through the resistor R2, a compensation signal Vc is input to the non-inverting input terminal of the first comparator 7 through the resistor R3, and an output terminal of the first comparator 7 serves as an output terminal of the current limiting unit 2 to output a current limiting signal Vi. Rs is connected in series in the loop of the switching tube S1 and the primary winding of the transformer, and is used for detecting the current of the switching tube S1. The detected current signal is input to the inverting input terminal of the first comparator 7, the preset current value Iref is input to the non-inverting input terminal of the first comparator 7 through the resistor R2, when the current of the switching tube S1 is greater than the preset current value Iref, the current limiting signal Vi is output to the drive generating unit 4, and the power supply circuit operates in a current limiting control state. When the detected current signal of the switching tube S1 is not greater than the preset current value Iref, the output current limiting signal Vi does not control the driving generation unit 4, and the driving generation unit 4 is controlled by the voltage stabilization unit 3. When the magnetic field unit 1 does not detect that the magnetic field strength exceeds the preset value, the compensation signal Vc cannot be output, and the current limiting unit 2 only works according to the working principle. When the magnetic field unit 1 detects that the magnetic field strength exceeds a preset value, a compensation signal Vc is output to the current limiting unit 2, and the compensation signal Vc and the preset current value Iref are superposed through R2 and R3 and then input to the non-inverting input end of the first comparator 7. Therefore, when the external magnetic field strength continuously increases, the amplitude of the compensation signal Vc output by the magnetic field unit 1 increases, and the amplitude of the signal input to the non-inverting input terminal of the first comparator 7 continuously increases, so that the amplitude of the current limiting signal Vi output by the current limiting unit 2 also continuously increases, the duty ratio of the driving signal generated by the driving generation unit 4 continuously increases, and the output power reduced due to strong magnetic interference is compensated. That is to say, when the external magnetic field of ammeter disturbed the ammeter, the change of parameter took place for the magnetic device of the supply circuit of ammeter, causes output to reduce, and output voltage reduces, and at this moment, make the electric current of switch tube S1 exceed the electric current default under the control of voltage stabilizing unit 3, and then supply circuit work is under the control of current limiting unit 2, and the current limiting unit 2 of this application has risen the duty cycle of switch tube S1 according to the compensation signal Vc of magnetic field unit, and then risees output voltage, compensate the ammeter because of the problem that outside strong magnetic field disturbed and arouse. It should be noted that the present embodiment exemplifies that the compensation signal Vc increases as the intensity of the external magnetic field increases. The same result can be obtained by superimposing Vc with the current signal (voltage on Rs) of the switching tube S1 through the resistor R3 and R2 after passing through the inverse follower, that is, the stronger the magnetism is, the larger the Vc amplitude is, after passing through the inverse follower, the smaller the amplitude thereof is, the smaller the value after superimposing is, and the input to the inverse input terminal of the first comparator 7 is also represented as the output current limiting signal Vi is increased.
Further, as shown in fig. 4, the current limiting unit 2 includes a second comparator 8, a third comparator 9, and resistors R9 and R10, an inverting input terminal of the second comparator 8 is connected to the resistor Rs for receiving the current detection signal, a current preset value Iref is input to a non-inverting input terminal of the second comparator 8 through the resistor R9, an inverting input terminal of the third comparator 9 is connected to a small voltage Vcs with an amplitude close to zero, the compensation signal Vc is input to the non-inverting input terminal of the third comparator 9, an output terminal of the third comparator 9 is connected to the non-inverting input terminal of the second comparator 8 through the resistor R10, and an output terminal of the second comparator 8 serves as an output terminal of the current limiting unit 2 for outputting the current limiting signal Vi.
As shown in fig. 5, the voltage stabilizing unit 3 includes a second operational amplifier 10 and a peripheral circuit, the peripheral circuit includes a capacitor C1 and resistors R4, R5, and R6, both ends of the resistors R4 and R5 are connected in series to both output ends of the power supply circuit, a common end of the resistors R4 and R5 is connected to an inverting input end of the second operational amplifier 10, one end of the resistor R6 is connected to the inverting input end of the second operational amplifier 10, the other end of the resistor R3624 is connected to an output end of the second operational amplifier 10 after being connected in series to the capacitor C1, the non-inverting input end of the second operational amplifier 10 inputs the preset voltage value Vref, and the output end of the second operational amplifier 10 serves as the output end of the voltage stabilizing unit 3 to output the feedback signal Vf.
As shown in fig. 6, the driving generation unit 4 is an SR flip-flop, a Q terminal of the SR flip-flop is used as an output terminal of the driving generation unit 4, and is configured to output a driving signal Vd, an output terminal S is connected to a control terminal of a switching tube S1 of the flyback main circuit, an input terminal R7 is connected to an output terminal of the current limiting unit 2, and is configured to receive a current limiting signal Vi, and an input terminal R8 is connected to an output terminal of the voltage stabilizing unit 3, and is configured to receive a feedback signal Vf.
The priority of the input terminal R7 is higher than that of the input terminal R8, that is, when R7 receives the trigger signal, the flip-flop starts to operate according to the signal of R7, and only when R7 does not receive the trigger signal, the flip-flop operates according to the signal received by R8.
Further, the control circuit also controls the flyback main circuit to work in a discontinuous mode. Specifically, when the power supply circuit is fully operated, the flyback main circuit operates in an intermittent mode. The discontinuous mode means: the sum of the duration Toff during which the secondary current of the transformer is not zero and the on-time Ton of the switching tube (i.e. the duration during which the primary current is not zero) is less than the switching period Tm.
As shown in fig. 7, the on-time Ton of the switching tube, the primary side current of the transformer, that Is, the current Is of the switching tube, the secondary side current Ir, and the duration Toff of the secondary side current, which Is not zero, are less than the switching period Tm of the switching tube. The flyback main circuit works in the discontinuous mode to ensure that the flyback main circuit can still work in the discontinuous mode when the maximum value of the signal is compensated.
The above description is only for the preferred embodiment of the present invention and should not be construed as limiting the present invention, and any modifications, equivalent replacements, and improvements made within the spirit and principle of the present invention are all included within the protection scope of the present invention.
Claims (9)
1. A power supply circuit of an electric meter comprises a flyback main circuit, wherein the flyback main circuit comprises a switching tube S1, a transformer T1, a resistor Rs, a diode D1 and a capacitor C1 which are connected with a secondary winding of the transformer T1 in series, the output end rectified by D1 and C1 serves as the output end of the power supply circuit, the resistor Rs is connected in series in a loop of the switching tube S1 and a primary winding of the transformer, and the voltage at two ends of the resistor Rs serves as a current detection signal of the switching tube S1, and the power supply circuit is characterized in that: the magnetic field control circuit further comprises a control circuit, wherein the control circuit comprises a magnetic field unit (1), a current limiting unit (2), a voltage stabilizing unit (3) and a drive generating unit (4);
the magnetic field unit (1) detects the intensity of a magnetic field, and when the detected intensity of the magnetic field exceeds a preset value, a compensation signal Vc is output to the current limiting unit (2);
the current limiting unit (2) compares a current detection signal of the switching tube S1 with a current preset value Iref, and outputs a current limiting signal Vi to the drive generating unit (4) when the current detection signal is greater than the current preset value Iref; and when receiving a compensation signal Vc output by the magnetic field unit (1), controlling the value of the current limiting signal Vi to increase along with the increase of the compensation signal Vc;
the voltage stabilizing unit (3) is used for detecting the output voltage Vo of the power supply circuit, presetting a preset voltage value Vref, and outputting a feedback signal Vf to the driving generation unit (4), wherein the feedback signal Vf represents the difference between the output voltage Vo and the preset voltage value Vref, and the voltage stabilizing unit (3) is used for controlling the output voltage to be equal to the preset voltage value Vref;
the drive generation unit (4) receives the current limiting signal Vi and the feedback signal Vf, and generates a drive signal Vd according to the feedback signal when only the feedback signal Vf is received, so that the duty ratio of the drive signal changes according to the change of the feedback signal; when receiving the current limit signal Vi, the driving signal Vd is generated based on the current limit signal, and the duty ratio of the driving signal is controlled to increase as the current limit signal Vi increases.
2. A supply circuit for an electricity meter, as claimed in claim 1, characterized in that: magnetic field unit (1) includes hall element H, first operational amplifier (5), triode Q1 and resistance R1, hall element H is supplied power by constant current source (6), and the input of first operational amplifier (5) is connected at both ends, and triode Q1's base is connected to the output of first operational amplifier (5), and constant current source (6) are connected to triode Q1's collecting electrode, ground connection behind emitter series resistance R1, the one end of resistance R1 non-ground connection is regarded as the output of magnetic field unit, voltage on the resistance R1 is compensation signal Vc.
3. A supply circuit for an electricity meter, as claimed in claim 2, characterized in that: the magnetic field unit further comprises a comparison unit, the comparison unit receives a slope signal of the current of the switching tube S1, compares the slope signal with a set value, and outputs a compensation signal Vc when the slope signal is greater than the set value.
4. A supply circuit for an electricity meter, as claimed in claim 3, characterized in that: the comparison unit also controls the amplitude of the compensation signal Vc output by the comparison unit to increase along with the increase of the slope signal.
5. A supply circuit for an electricity meter, as claimed in claim 1, characterized in that: the current limiting unit (2) comprises a first comparator (7), resistors R2 and R3, wherein the inverting input end of the first comparator (7) is connected with the resistor Rs and used for receiving the current detection signal, a current preset value Iref is input to the non-inverting input end of the first comparator (7) through the resistor R2, a compensation signal Vc is input to the non-inverting input end of the first comparator (7) through the resistor R3, and the output end of the first comparator (7) serves as the output end of the current limiting unit (2) and outputs a current limiting signal Vi.
6. A supply circuit for an electricity meter, as claimed in claim 1, characterized in that: the current limiting unit (2) comprises a second comparator (8), a third comparator (9) and resistors R9 and R10, wherein the reverse phase input end of the second comparator (8) is connected with the resistor Rs and used for receiving the current detection signal, a current preset value Iref is input to the positive phase input end of the second comparator (8) through the resistor R9, the reverse phase input end of the third comparator (9) is connected with a small voltage Vcs with the amplitude close to zero, a compensation signal Vc is input to the positive phase input end of the third comparator (9), the output end of the third comparator (9) is connected with the positive phase input end of the second comparator (8) through the resistor R10, and the output end of the second comparator (8) serves as the output end of the current limiting unit (2) and outputs a current limiting signal Vi.
7. A supply circuit for an electricity meter, as claimed in claim 1, characterized in that: the voltage stabilizing unit (3) comprises a second operational amplifier (10) and a peripheral circuit, the peripheral circuit comprises a capacitor C1 and resistors R4, R5 and R6, two ends of the resistors R4 and R5 are connected to two output ends of the power supply circuit respectively after being connected in series, a common end of the resistors R4 and R5 is connected with an inverting input end of the second operational amplifier (10), one end of the resistor R6 is connected with the inverting input end of the second operational amplifier (10), the other end of the resistor R3624 is connected with an output end of the second operational amplifier (10) after being connected in series with the capacitor C1, the non-inverting input end of the second operational amplifier (10) inputs the voltage preset value Vref, and the output end of the second operational amplifier (10) serves as the output end of the voltage stabilizing unit (3) to output a feedback signal Vf.
8. A supply circuit for an electricity meter, as claimed in claim 1, characterized in that: the driving generation unit (4) is an SR trigger, a Q end of the SR trigger serves as an output end of the driving generation unit (4) and is used for outputting a driving signal Vd, an output end S is connected with a control end of a switching tube S1 of the flyback main circuit, an input end R7 is connected with an output end of the current limiting unit (2) and is used for receiving a current limiting signal Vi, and an input end R8 is connected with an output end of the voltage stabilizing unit (3) and is used for receiving a feedback signal Vf.
9. A power supply circuit for an electricity meter in accordance with claim 8, wherein: the input terminal R7 has a higher priority than the input terminal R8.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201922337824.9U CN210839350U (en) | 2019-12-23 | 2019-12-23 | Power supply circuit of ammeter |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201922337824.9U CN210839350U (en) | 2019-12-23 | 2019-12-23 | Power supply circuit of ammeter |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN210839350U true CN210839350U (en) | 2020-06-23 |
Family
ID=71260744
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201922337824.9U Active CN210839350U (en) | 2019-12-23 | 2019-12-23 | Power supply circuit of ammeter |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN210839350U (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115808611A (en) * | 2022-12-13 | 2023-03-17 | 深圳市耀星微电子有限公司 | Integrated circuit test system |
-
2019
- 2019-12-23 CN CN201922337824.9U patent/CN210839350U/en active Active
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115808611A (en) * | 2022-12-13 | 2023-03-17 | 深圳市耀星微电子有限公司 | Integrated circuit test system |
| CN115808611B (en) * | 2022-12-13 | 2023-11-17 | 深圳市耀星微电子有限公司 | Integrated circuit test system |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US10241143B2 (en) | Sensing resistor short determiner, switch control circuit including the same and power supply including the switch control circuit | |
| US6646894B2 (en) | Switching mode power supply | |
| CN102739079B (en) | Power circuit | |
| US8085007B2 (en) | Switching power supply circuit | |
| KR100829121B1 (en) | Single Stage Power Factor Correction Circuit by Boundary Conduction Mode | |
| CN110165901A (en) | Control circuit, switch mode power and corresponding control method | |
| TWI533745B (en) | Light source driving circuit, controller and method for controlling power converter | |
| US10491124B2 (en) | BiFRED converter and a method of driving an output load | |
| WO2015111006A1 (en) | Switching-mode power supplies | |
| CN104283430A (en) | Soft start switching power supply conversion device | |
| CN210839350U (en) | Power supply circuit of ammeter | |
| JP4339129B2 (en) | Switch mode power supply | |
| CN205753993U (en) | Switching Power Supply and electronic installation | |
| WO2021109561A1 (en) | Charging circuit, charging device, and display screen | |
| CN216290170U (en) | B-type residual current operated protective circuit breaker | |
| CN102857126A (en) | Control circuit of power converter | |
| CN109039112B (en) | Primary side feedback switching power supply control chip, control system and charger | |
| CN110868070A (en) | Power supply circuit of ammeter | |
| CN103904871A (en) | Control method of high-frequency heating power switch tube protection circuit | |
| CN217465816U (en) | Error signal eliminating circuit and sensor | |
| CN114460883B (en) | OCC driver with voltage dynamically controllable adjustment based on double-loop control | |
| CN214850518U (en) | Capacitor charging control circuit, power factor correction circuit and air conditioner | |
| CN105119468A (en) | Control circuit of power converter and method therefore | |
| CN209994279U (en) | Switch power supply | |
| US20090108818A1 (en) | Switching power supply circuit |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| GR01 | Patent grant | ||
| GR01 | Patent grant |