Super capacitor management circuit

Abstract

The utility model discloses a super capacitor management circuit comprising a wiring terminal, the wiring terminal is electrically connected with a charging circuit and a discharging circuit, the discharging circuit is electrically connected with a power conversion circuit, and the power conversion circuit is electrically connected with a discharging management circuit. According to the utility model, the charging current-limiting resistor of the super capacitor is realized through an external connection mode of the wiring terminal, flexible configuration can be realized through a mode of configuring an external resistor, and the flexibility is high; when the super capacitor discharges to a critical point, the system cannot be repeatedly started, and the reliability is high; a system power supply can be thoroughly turned off, and related problems caused by abnormal power supply are avoided; the power failure time of the system from the working voltage to 0V is short, and the monotonicity of the power failure of the system power supply can be ensured.

Description

Technical Field

[0001] The utility model relates to the field of electricity, in particular to a supercapacitor management circuit. Background Art

[0002] Supercapacitors are currently widely used in short-term backup power management systems due to their low cost, maintenance-free, and high reliability. Commonly, in many low-cost supercapacitor management circuits, such as Figure 1 As shown, a fixed current limiting resistor R1 is directly used for charge management, and then a Schottky diode D1 is used for discharge management.

[0003] The biggest advantage of the above supercapacitor management circuit is its low cost, but it also has a series of problems, mainly:

[0004] 1. The charging current limiting resistor is fixed and not easy to configure flexibly.

[0005] 2. When the capacitor is discharged to the critical point, the system has the problem of repeated startup due to load changes.

[0006] 3. No hysteresis characteristics, poor system reliability.

[0007] 4. The system cannot quickly power down from the operating voltage to 0V, and the intermediate level can last for several minutes or even longer, indicating an abnormal power supply problem. Utility Model Content

[0008] In order to solve the above technical problems, the utility model proposes a supercapacitor management circuit.

[0009] The purpose of the utility model is achieved through the following technical solutions:

[0010] A supercapacitor management circuit comprises a connection terminal CON1, wherein the connection terminal CON1 is electrically connected to a charging circuit, a discharging circuit and a supercapacitor C, the discharging circuit is electrically connected to a power conversion circuit, and the power conversion circuit is electrically connected to a discharge management circuit.

[0011] As a further improvement, the wiring terminal CON1 includes an R+ terminal, a CAP+ / R- terminal and a CAP- terminal; the charging circuit includes a current limiting resistor R, one end of the current limiting resistor R is electrically connected to the R+ terminal, and the other end is electrically connected to the CAP+ / R- terminal; the negative electrode of the supercapacitor C is electrically connected to the CAP- terminal, and the positive electrode is electrically connected to the CAP+ / R- terminal; wherein the positive electrode of the supercapacitor and the other end of the current limiting resistor share the wiring terminal CAP+ / R-.

[0012] As a further improvement, the discharge circuit includes a Schottky diode D1, the anode of the Schottky diode D1 is electrically connected to the CAP+ / R- terminal, and the cathode of the Schottky diode D1 is electrically connected to the power conversion circuit and the discharge management circuit.

[0013] As a further improvement, the power conversion circuit includes a system power conversion module M2, a voltage input terminal of the system power conversion module M2 is electrically connected to the cathode of the Schottky diode D1, an enable terminal of the system power conversion module M2 is electrically connected to one end of the fifth resistor R5, and the other end of the fifth resistor R5 is grounded.

[0014] As a further improvement, the system power conversion module M2 is a power conversion chip XC8128QXA produced by Zhuzhou Hongda.

[0015] As a further improvement, the discharge management circuit includes a normal power supply conversion module M1 and a first resistor R1, the voltage input end of the normal power supply conversion module M1 is electrically connected to the cathode of the Schottky diode D1, and the voltage output end is electrically connected to one end of the third resistor R3 and the first cathode of the voltage comparator U1; the first anode of the voltage comparator U1 is grounded; the other end of the third resistor R3 is electrically connected to one end of the fourth resistor R4 and the second cathode of the voltage comparator U1, and the other end of the fourth resistor R4 is grounded; one end of the first resistor R1 is electrically connected to the cathode of the Schottky diode D1, and the other end is electrically connected to one end of the second resistor R2 and one end of the input resistor RS1; the other end of the second resistor R2 is grounded, the other end of the input resistor RS1 is electrically connected to the second anode of the voltage comparator U1 and one end of the feedback resistor RF1, and the other end of the feedback resistor RF1 is electrically connected to the output end of the voltage comparator U1, one end of the fifth resistor R5 and the enable end of the system power supply conversion module M2.

[0016] As a further improvement, the normal power supply conversion module M1 is a power conversion chip XC9828ASNA produced by Zhuzhou Hongda.

[0017] The beneficial effects of the utility model are:

[0018] 1. The supercapacitor charging current limiting resistor is realized through external connection of the terminal block, and can be flexibly configured by configuring the external resistor, which is highly flexible.

[0019] 2. It has hysteresis characteristics. When the supercapacitor is discharged to the critical point, the system will not start repeatedly, and the reliability is high.

[0020] 3. The system power supply can be completely shut down to avoid problems caused by abnormal power supply.

[0021] 4. The system has a fast power-off time from the working voltage to 0V, which can ensure the monotonicity of the system power failure. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The present invention is further described with reference to the accompanying drawings, but the contents in the accompanying drawings do not constitute any limitation to the present invention.

[0023] Figure 1 For the wiring terminal;

[0024] Figure 2 It is the supercapacitor management circuit. DETAILED DESCRIPTION

[0025] In order to make the purpose, technical solution and advantages of the utility model more clear, the utility model is further described in detail below with reference to the accompanying drawings and examples.

[0026] Example 1

[0027] like Figure 2 The supercapacitor management circuit shown is mainly composed of five parts: a charging circuit, a discharging circuit, a power conversion circuit, a discharge management circuit and a wiring terminal.

[0028] For the charging circuit, it is mainly realized by connecting a current limiting resistor R on the outside of the terminal CON1, and the current limiting resistor is connected between the R+ and CAP+ / R- terminals of the terminal CON1. ​​Different current limiting resistors can be configured for different charging requirements, which is convenient and flexible. In addition, the supercapacitor C is connected between the CAP+ / R- and CAP- terminals of the terminal CON1, where the positive electrode of the supercapacitor and one pin of the current limiting resistor share the terminal CAP+ / R-, which can effectively reduce the wiring length and reduce line loss while saving the terminal.

[0029] The discharge circuit is mainly implemented by Schottky diode D1, which has the characteristic of low voltage difference.

[0030] The power conversion circuit is mainly composed of a system power conversion module M2 and a state preset resistor R5. The conversion module mainly converts the unstable power after the discharge circuit into a stable system power for stable operation of the system. In addition, the enable end of the system power conversion module M2 is controlled by the discharge management circuit.

[0031] The discharge management circuit is composed of two circuits: a normal power supply conversion module M1 and a voltage comparator. The normal power supply conversion module M1 provides a stable power supply to the voltage comparator circuit. The voltage comparator circuit is composed of a voltage comparator U1, voltage divider resistors R1, R2, R3, R4, input resistor RS1 and feedback resistor RF1. The voltage comparator reference voltage VREF is 3V3*R4 / (R3+R4). When the external power supply is lost and discharged by the super capacitor, when the VSYS voltage is lower than (R1+R2) / R2*(RS / RF*(VREF-VOH)+VREF), the comparator circuit outputs a low level, so that the system power conversion module M2 stops working; when the external power supply returns to normal, VSYS is approximately equal to the external power supply voltage, higher than the comparison voltage (R1+R2) / R2*(RS / RF*(VREF-VOL)+VREF), and the comparator circuit outputs a high level, so that the system power conversion module M2 works normally.

[0032] The utility model discloses a supercapacitor management circuit, in which a supercapacitor charging current limiting resistor is realized by externally connecting a wiring terminal, and a flexible configuration can be realized by configuring an external resistor, and a specific wiring method is between two terminals R+ and CAP+ / R- of a wiring terminal CON1.

[0033] The utility model discloses a supercapacitor management circuit with hysteresis characteristics. When the voltage of the supercapacitor after passing through the discharge circuit is lower than (R1+R2) / R2*(RS / RF*(VREF-VOH)+VREF), the discharge stops. At this time, due to the load change, the supercapacitor voltage rises, but through parameter setting, it will not be higher than (R1+R2) / R2*(RS / RF*(VREF-VOL)+VREF), so the system power conversion module M2 will not re-output; only when the external power supply is connected, the VSYS voltage is higher than (R1+R2) / R2*(RS / RF*(VREF-VOL)+VREF), the system power conversion module M2 will re-output, and VSYS will charge the supercapacitor through the charging circuit. The above ensures that when the supercapacitor is discharged to a critical state, the system will not start repeatedly, effectively improving the reliability of the system.

[0034] The utility model discloses a supercapacitor management circuit. When the discharge management circuit outputs a low level to shut down the system power conversion module M2, the back-stage SYS_3V3 quickly reduces the working voltage to 0V, thereby ensuring the monotonicity of the power supply, preventing the system from having long-term abnormal power supply problems, and improving the reliability of the system.

[0035] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the utility model rather than to limit the protection scope of the utility model. Although the utility model is described in detail with reference to the preferred embodiments, ordinary technicians in this field should understand that the technical solution of the utility model can be modified or replaced by equivalents without departing from the essence and scope of the technical solution of the utility model.

Claims

1. A supercapacitor management circuit, characterized in that: The invention comprises a wiring terminal (CON1), wherein the wiring terminal (CON1) is electrically connected to a charging circuit, a discharging circuit and a super capacitor (C), wherein the discharging circuit is electrically connected to a power conversion circuit, and wherein the power conversion circuit is electrically connected to a discharge management circuit; the wiring terminal (CON1) comprises an R+ terminal, a CAP+ / R- terminal and a CAP- terminal; the charging circuit comprises a current limiting resistor (R), wherein one end of the current limiting resistor (R) is electrically connected to the R+ terminal, and the other end is electrically connected to the CAP+ / R- terminal; the negative electrode of the super capacitor (C) is electrically connected to the CAP- terminal, and the positive electrode is electrically connected to the CAP+ / R- terminal. -end; wherein the positive electrode of the supercapacitor and the other end of the current limiting resistor share a wiring terminal CAP+ / R-; the discharge circuit comprises a Schottky diode (D1), the positive electrode of the Schottky diode (D1) is electrically connected to the CAP+ / R-end, and the negative electrode is electrically connected to the power conversion circuit and the discharge management circuit; the power conversion circuit comprises a system power conversion module (M2), the voltage input end of the system power conversion module (M2) is electrically connected to the negative electrode of the Schottky diode (D1), and the enable end of the system power conversion module (M2) is electrically connected to one end of a fifth resistor (R5), The other end of the fifth resistor (R5) is grounded; the discharge management circuit comprises a normal power supply conversion module (M1) and a first resistor (R1); the voltage input end of the normal power supply conversion module (M1) is electrically connected to the cathode of the Schottky diode (D1), and the voltage output end is electrically connected to one end of the third resistor (R3) and the first cathode of the voltage comparator (U1); the first anode of the voltage comparator (U1) is grounded; the other end of the third resistor (R3) is electrically connected to one end of the fourth resistor (R4) and the second cathode of the voltage comparator (U1); 4) is grounded; one end of the first resistor (R1) is electrically connected to the cathode of the Schottky diode (D1), and the other end is electrically connected to one end of the second resistor (R2) and one end of the input resistor (RS1); the other end of the second resistor (R2) is grounded, the other end of the input resistor (RS1) is electrically connected to the second anode of the voltage comparator (U1) and one end of the feedback resistor (RF1), and the other end of the feedback resistor (RF1) is electrically connected to the output end of the voltage comparator (U1), one end of the fifth resistor (R5) and the enable end of the system power conversion module (M2).

2. The supercapacitor management circuit according to claim 1, characterized in that: The system power conversion module M2 is a power conversion chip XC8128QXA produced by Zhuzhou Hongda.

3. The supercapacitor management circuit according to claim 1, characterized in that: The normal power supply conversion module (M1) is a power conversion chip XC9828ASNA produced by Zhuzhou Hongda.

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