CN113866491B - Winding driving circuit overcurrent detection circuit and design method thereof - Google Patents
Winding driving circuit overcurrent detection circuit and design method thereof Download PDFInfo
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- CN113866491B CN113866491B CN202111051963.0A CN202111051963A CN113866491B CN 113866491 B CN113866491 B CN 113866491B CN 202111051963 A CN202111051963 A CN 202111051963A CN 113866491 B CN113866491 B CN 113866491B
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- 238000001514 detection method Methods 0.000 title claims abstract description 29
- 238000004804 winding Methods 0.000 title claims abstract description 29
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- 230000003321 amplification Effects 0.000 claims abstract description 6
- 238000003199 nucleic acid amplification method Methods 0.000 claims abstract description 6
- 238000005070 sampling Methods 0.000 claims description 24
- 238000006243 chemical reaction Methods 0.000 claims description 13
- 239000003990 capacitor Substances 0.000 claims description 12
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- 230000009286 beneficial effect Effects 0.000 description 1
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R19/00—Arrangements for measuring currents or voltages or for indicating presence or sign thereof
- G01R19/165—Indicating that current or voltage is either above or below a predetermined value or within or outside a predetermined range of values
- G01R19/16566—Circuits and arrangements for comparing voltage or current with one or several thresholds and for indicating the result not covered by subgroups G01R19/16504, G01R19/16528, G01R19/16533
- G01R19/16571—Circuits and arrangements for comparing voltage or current with one or several thresholds and for indicating the result not covered by subgroups G01R19/16504, G01R19/16528, G01R19/16533 comparing AC or DC current with one threshold, e.g. load current, over-current, surge current or fault current
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R1/00—Details of instruments or arrangements of the types included in groups G01R5/00 - G01R13/00 and G01R31/00
- G01R1/30—Structural combination of electric measuring instruments with basic electronic circuits, e.g. with amplifier
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Abstract
The invention belongs to the technical field of high-side drive overcurrent detection, and particularly relates to a winding drive circuit overcurrent detection circuit and a design method thereof. The detection circuit includes: the voltage follower circuit, the amplification adjusting circuit and the current follower circuit can bear high-side power supply surge and peak and have lower cost. Meanwhile, a design method for the detection circuit is also provided, so that the detection circuit is easy to realize and is suitable for an airborne electronic environment.
Description
Technical Field
The invention belongs to the technical field of high-side drive overcurrent detection, and particularly relates to a winding drive circuit overcurrent detection circuit and a design method thereof, wherein the winding drive circuit overcurrent detection circuit is mainly used when a high-side power supply surge exists in the overcurrent of a high-side drive circuit.
Background
The high-side driving circuit is widely applied in the fields of power electronics and the like, overcurrent protection of the driving circuit is important, the fault detection circuit is positioned at the front edge of the protection circuit and is generally positioned near the detected circuit, the current of the detected circuit is detected, and the detected information is sent to the driving control circuit in a voltage mode.
At present, the voltage at two ends of a sampling resistor is mainly collected through an operational amplifier and converted into corresponding amplified voltage, the operational amplifier is easy to be interfered by a high-side driving male mode due to the fact that the operational amplifier is positioned at a high side, the operational amplifier is difficult to supply power, the peak and surge voltage of a high-side power supply can be born, the system cost is high, the circuit structure is complex, the fault detection performance is poor, and practical application is limited. Therefore, it is desirable to design an overcurrent detection method that can withstand high-side power surges, spikes, and at a low cost.
Disclosure of Invention
In view of this, the present invention provides a winding driving circuit overcurrent detection circuit which has simple design, easy implementation, strong anti-interference capability and can effectively detect overcurrent faults, and the winding driving circuit overcurrent detection circuit comprises:
the voltage follower circuit is used for following the low-voltage terminal voltage of the sampling resistor;
the amplifying and adjusting circuit is used for ensuring that the voltage follower circuit and the current follower circuit work normally;
and the current follower circuit is used for converting the sampling resistor current with higher common-mode voltage into the sampling circuit without the common-mode voltage.
Further, the voltage follower circuit comprises a first PNP triode and a diode; the collector electrode of the first PNP triode is connected with the base electrode of the first PNP triode; the two ends of the diode are respectively connected with the collector and the emitter of the first PNP triode, and the direction of the diode is from the collector to the emitter;
the following voltage of the voltage following circuit is reduced along with the increase of the sampling current and is increased along with the decrease of the current; the diode is used for protecting the collector electrode and the emitter electrode of the first PNP triode from being damaged when impact current arrives.
Further, the amplification adjusting circuit comprises a second PNP triode and a resistor R4; one end of the resistor R4 is connected with the emitter of the second PNP triode, and the other end of the resistor R4 is connected with digital ground; the base electrode of the second PNP triode is connected with a digital +5V, and the collector electrode of the second PNP triode is connected with the current follower circuit;
the amplifying and adjusting circuit is used for automatically adjusting the amplifying state according to the voltage transformation of the voltage follower circuit, so that the first PNP triode and the triode in the current follower circuit are positioned in the amplifying region.
Further, the current follower circuit comprises a conversion resistor R1, a capacitor C1 and an NPN triode, wherein one end of the conversion resistor R1 is connected with a high-side power supply, and the other end of the conversion resistor R1 is connected with an emitter of the NPN triode; two ends of the capacitor C1 are respectively connected with the base electrode and the emitter electrode of the NPN triode; the collector electrode of the second PNP triode is connected with the base electrode of the NPN triode;
the current follower circuit is used for following the voltage conversion of the sampling resistor to two ends of the conversion resistor and forming current, and converting the current into a required voltage value according to the amplification requirement.
Further, in the overcurrent state of the winding driving circuit, the method for making the first PNP triode be in the amplifying region is as follows:
the voltage drop of the overcurrent I at the sampling resistor R0 is greater than 0.7V.
Meanwhile, the invention also provides a design method of the winding driving circuit overcurrent detection circuit, which comprises the following steps:
step 1: according to the overcurrent I, a reasonable sampling resistance value R0 is selected by combining a formula R0 x I > 0.7;
step 2: setting the resistance R1 to be not more than 1KΩ;
step 3: selecting proper R3 according to the output current value R0I/R1 of the current follower circuit and the required voltage value;
step 4: and selecting proper R2 according to R3 and the output current value R0I/R1 of the current follower circuit and combining triode characteristics.
By adopting the technical scheme, the invention has the following beneficial effects:
the invention provides a high-side overcurrent detection method of a winding driving circuit, which comprises the following steps: and detecting the winding overcurrent state at the high side by using an overcurrent detection circuit, and controlling the field tube driver by a drive control logic according to the overcurrent detection state and the actual working requirement to control the working state of the winding so as to protect the field effect tube and the winding from working in the non-overcurrent state. The high-side winding overcurrent detection circuit comprises a voltage following function, a current following function, an amplifying and adjusting function and a current collecting function, wherein the voltage following function is used for obtaining winding overcurrent at a high side and converting the winding overcurrent into a voltage signal, the current following function is used for converting the voltage signal into a collectable current signal and transmitting the current to the current collecting function, the voltage conversion of the overcurrent detection current is realized, and the amplifying and adjusting function ensures that the voltage following function module and the current following function are in a normal working state. The voltage following function and the current following function are realized by using triodes, and can bear high-side power supply surge. The invention has simple design, easy realization and strong anti-interference capability, can effectively detect the overcurrent of the winding driving circuit, and is particularly suitable for the airborne electronic environment.
Drawings
In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings that are needed in the embodiments will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and that other drawings can be obtained according to these drawings without inventive effort for a person skilled in the art.
FIG. 1 is a schematic diagram of the overall connection of a winding driver circuit with a current detection circuit in an embodiment of the present invention;
fig. 2 is a schematic circuit diagram of an overcurrent detection circuit according to an embodiment of the invention.
Detailed Description
Embodiments of the present invention will be described in detail below with reference to the accompanying drawings.
Other advantages and effects of the present invention will become apparent to those skilled in the art from the following disclosure, which describes the embodiments of the present invention with reference to specific examples. It will be apparent that the described embodiments are only some, but not all, embodiments of the invention. The invention may be practiced or carried out in other embodiments that depart from the specific details, and the details of the present description may be modified or varied from the spirit and scope of the present invention. It should be noted that the following embodiments and features in the embodiments may be combined with each other without conflict. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.
It is noted that various aspects of the embodiments are described below within the scope of the following claims. It should be apparent that the aspects described herein may be embodied in a wide variety of forms and that any specific structure and/or function described herein is merely illustrative. Based on the present disclosure, one skilled in the art will appreciate that one aspect described herein may be implemented independently of any other aspect, and that two or more of these aspects may be combined in various ways. For example, an apparatus may be implemented and/or a method practiced using any number of the aspects set forth herein. In addition, such apparatus may be implemented and/or such methods practiced using other structure and/or functionality in addition to one or more of the aspects set forth herein.
It should also be noted that the illustrations provided in the following embodiments merely illustrate the basic concept of the present invention by way of illustration, and only the components related to the present invention are shown in the drawings and are not drawn according to the number, shape and size of the components in actual implementation, and the form, number and proportion of the components in actual implementation may be arbitrarily changed, and the layout of the components may be more complicated.
In addition, in the following description, specific details are provided in order to provide a thorough understanding of the examples. However, it will be understood by those skilled in the art that the aspects may be practiced without these specific details.
In one embodiment of the present invention, a winding driving circuit overcurrent detection circuit applied to the scenario shown in fig. 1 is provided, as shown in fig. 2, including:
the voltage follower circuit is used for following the low-voltage terminal voltage of the sampling resistor;
the amplifying and adjusting circuit is used for ensuring that the voltage follower circuit and the current follower circuit work normally;
and the current follower circuit is used for converting the sampling resistor current with higher common-mode voltage into the sampling circuit without the common-mode voltage.
In this embodiment, as shown in fig. 2, the voltage follower circuit includes a first PNP transistor and a diode; the collector electrode of the first PNP triode is connected with the base electrode of the first PNP triode; the two ends of the diode are respectively connected with the collector and the emitter of the first PNP triode, and the direction of the diode is from the collector to the emitter;
the following voltage of the voltage following circuit is reduced along with the increase of the sampling current and is increased along with the decrease of the current; the diode is used for protecting the collector electrode and the emitter electrode of the first PNP triode from being damaged when impact current arrives.
In this embodiment, as shown in fig. 2, the amplifying and adjusting circuit includes a second PNP transistor and a resistor R4; one end of the resistor R4 is connected with the emitter of the second PNP triode, and the other end of the resistor R4 is connected with digital ground; the base electrode of the second PNP triode is connected with a digital +5V, and the collector electrode of the second PNP triode is connected with the current follower circuit;
the amplifying and adjusting circuit is used for automatically adjusting the amplifying state according to the voltage transformation of the voltage follower circuit, so that the first PNP triode and the triode in the current follower circuit are positioned in the amplifying region.
In this embodiment, as shown in fig. 2, the current follower circuit includes a scaling resistor R1, a capacitor C1 and an NPN triode, wherein one end of the scaling resistor R1 is connected to a high-side power supply, and the other end is connected to an emitter of the NPN triode; two ends of the capacitor C1 are respectively connected with the base electrode and the emitter electrode of the NPN triode; the collector electrode of the second PNP triode is connected with the base electrode of the NPN triode;
the current follower circuit is used for following the voltage conversion of the sampling resistor to two ends of the conversion resistor and forming current, and converting the current into a required voltage value according to the amplification requirement.
In this embodiment, as shown in fig. 2, in the overcurrent state of the winding driving circuit, the method for making the first PNP transistor be in the amplifying region is as follows:
the voltage drop of the overcurrent I at the sampling resistor R0 is greater than 0.7V.
As shown in fig. 2, the collector terminal of the NPN triode is connected to one end of the resistor R2; the other end of the resistor R2 is connected with control driving logic, one end of the resistor R3 and one end of the capacitor C2; wherein the other end of the resistor R3 and the other end of the capacitor C2 are grounded.
In one embodiment, a design method of the winding driving circuit overcurrent detection circuit is provided, which includes the following steps:
step 1: according to the overcurrent I, a reasonable sampling resistance value R0 is selected by combining a formula R0 x I > 0.7;
step 2: setting the resistance R1 to be not more than 1KΩ;
step 3: selecting proper R3 according to the output current value R0I/R1 of the current follower circuit and the required voltage value;
step 4: and selecting proper R2 according to R3 and the output current value R0I/R1 of the current follower circuit and combining triode characteristics.
The present embodiment has the following four scenarios in the course of operation:
scene 1: when winding current i=0, that is, no current passes through the "current sampling resistor" R0, the triode V1 is turned on, the triode V2 is turned on, the voltage of the emitter V2 is +50v, the voltage of the base V2 is about +49.3v, the triode V3 is in an off state, and the voltage at two ends of R3 is 0V.
Scene 2: when the winding current I increases gradually (I increases gradually), that is, when a current passes through the "current sampling resistor" R0, the voltage across the resistor R0 is "R0I", the transistor V1 is turned on, the transistor V2 is turned on, the voltage across the emitter of V2 is "50V-R0I", the voltage across the base of V2 is about "49.3V-R0I", the transistor V3 is turned on gradually, the emitter and collector currents of the transistor V3 are substantially equal, and both are about equal to "R0I/R1", so that the voltage across the R3 is "R0I/R1R 3". When winding current i=0, the voltage across R3 is also "R0I/R1R 3".
Scene 3: when the winding current I increases to I V2, the voltage across the resistor R0 is "R0 x I V2", the transistor V1 is turned on, the transistor V3 is turned on, the transistor V2 is in an off state, i.e., the voltage across the emitter of V3 is greater than the voltage across the emitter of V2, but V4 is not triggered to be turned on, and at this time, the voltage across the resistor R3 is greater than the voltage across the resistor R3 in case 2.
Scene 4: when the winding current I continuously increases, the triode V1 is conducted, the triode V3 is conducted, the triode V2 is in a cut-off state, the V4 diode is conducted, the V2 is protected from being broken down by collector and emitter voltages, and the voltage at two ends of R3 is "(R0I-2.1)/R1R 3).
In combination with scenario 1, scenario 2, scenario 3, and scenario 4, it is necessary to ensure that the overcurrent detection circuit operates in scenario 1 and scenario 2 in a non-overcurrent state. The capacitor C1 is used for protecting the triode V3, and the capacitor C2 is used for confirming the overcurrent time and filtering out the overcurrent burrs.
The foregoing is merely illustrative of the present invention, and the present invention is not limited thereto, and any changes or substitutions easily contemplated by those skilled in the art within the scope of the present invention should be included in the present invention. Therefore, the protection scope of the invention is subject to the protection scope of the claims.
Claims (3)
1. A winding drive circuit overcurrent detection circuit, characterized by comprising:
the voltage follower circuit is used for following the low-voltage terminal voltage of the sampling resistor;
the amplifying and adjusting circuit is used for ensuring that the voltage follower circuit and the current follower circuit work normally;
the current follower circuit is used for converting the sampling resistor current with higher common-mode voltage into a sampling circuit without common-mode voltage;
wherein:
the voltage follower circuit comprises a first PNP triode and a diode; the collector electrode of the first PNP triode is connected with the base electrode of the first PNP triode; the two ends of the diode are respectively connected with the collector and the emitter of the first PNP triode, and the direction of the diode is from the collector to the emitter;
the following voltage of the voltage following circuit is reduced along with the increase of the sampling current and is increased along with the decrease of the current; the diode is used for protecting the collector electrode and the emitter electrode of the first PNP triode from being damaged when the impact current arrives;
the amplification adjusting circuit comprises a second PNP triode and a resistor R4; one end of the resistor R4 is connected with the emitter of the second PNP triode, and the other end of the resistor R4 is connected with digital ground; the base electrode of the second PNP triode is connected with a digital +5V, and the collector electrode of the second PNP triode is connected with the current follower circuit;
the amplifying and adjusting circuit is used for automatically adjusting the amplifying state according to the voltage transformation of the voltage follower circuit so that the first PNP triode and the triode in the current follower circuit are positioned in an amplifying area;
the current follower circuit comprises a conversion resistor R1, a capacitor C1 and an NPN triode, wherein one end of the conversion resistor R1 is connected with a high-side power supply, and the other end of the conversion resistor R1 is connected with an emitter of the NPN triode; two ends of the capacitor C1 are respectively connected with the base electrode and the emitter electrode of the NPN triode; the collector electrode of the second PNP triode is connected with the base electrode of the NPN triode;
the current follower circuit is used for following the voltage conversion of the sampling resistor to two ends of the conversion resistor and forming current, and converting the current into a required voltage value according to the amplification requirement;
the collector terminal of the NPN triode is connected with one end of a resistor R2; the other end of the resistor R2 is connected with control driving logic, one end of the resistor R3 and one end of the capacitor C2; wherein the other end of the resistor R3 and the other end of the capacitor C2 are grounded.
2. The overcurrent detection circuit of claim 1, wherein: when the winding driving circuit is in an overcurrent state, the method for enabling the first PNP triode to be in an amplifying region comprises the following steps of:
the voltage drop of the overcurrent I at the sampling resistor R0 is greater than 0.7V.
3. The method of designing a winding drive circuit overcurrent detection circuit according to claim 1 or 2, comprising the steps of:
step 1: according to the overcurrent I, a reasonable sampling resistance value R0 is selected by combining a formula R0 x I > 0.7;
step 2: setting the resistance R1 to be not more than 1KΩ;
step 3: selecting proper R3 according to the output current value R0I/R1 of the current follower circuit and the required voltage value;
step 4: and selecting proper R2 according to R3 and the output current value R0I/R1 of the current follower circuit and combining triode characteristics.
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| CN202111051963.0A CN113866491B (en) | 2021-09-08 | 2021-09-08 | Winding driving circuit overcurrent detection circuit and design method thereof |
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| Application Number | Priority Date | Filing Date | Title |
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| CN202111051963.0A CN113866491B (en) | 2021-09-08 | 2021-09-08 | Winding driving circuit overcurrent detection circuit and design method thereof |
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| CN113866491B true CN113866491B (en) | 2024-02-20 |
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Citations (4)
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|---|---|---|---|---|
| JP2005341730A (en) * | 2004-05-27 | 2005-12-08 | Murata Mfg Co Ltd | Overcurrent protective circuit |
| CN203787935U (en) * | 2014-04-09 | 2014-08-20 | 太原科技大学 | Over-current protection circuit based on high side current detection |
| CN206389309U (en) * | 2017-01-24 | 2017-08-08 | 重庆新和平自动化有限公司 | The stepper motor driving circuit protected with over-current detection |
| CN112255451A (en) * | 2020-12-21 | 2021-01-22 | 上海芯龙半导体技术股份有限公司南京分公司 | Overcurrent detection circuit, overcurrent protection circuit and switching power supply |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP7087373B2 (en) * | 2017-12-20 | 2022-06-21 | 富士電機株式会社 | Current detection circuit and current detection method for semiconductor devices |
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2021
- 2021-09-08 CN CN202111051963.0A patent/CN113866491B/en active Active
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2005341730A (en) * | 2004-05-27 | 2005-12-08 | Murata Mfg Co Ltd | Overcurrent protective circuit |
| CN203787935U (en) * | 2014-04-09 | 2014-08-20 | 太原科技大学 | Over-current protection circuit based on high side current detection |
| CN206389309U (en) * | 2017-01-24 | 2017-08-08 | 重庆新和平自动化有限公司 | The stepper motor driving circuit protected with over-current detection |
| CN112255451A (en) * | 2020-12-21 | 2021-01-22 | 上海芯龙半导体技术股份有限公司南京分公司 | Overcurrent detection circuit, overcurrent protection circuit and switching power supply |
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| Title |
|---|
| A novel over-current protection circuit for LED constant current driver;Sun Yuqing et al.;《2015 IEEE 16th International Conference on Communication Technology》;第225-228页 * |
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