Auxiliary indicating circuit matched with charging IC

Abstract

An auxiliary indicating circuit matched with a charging IC comprises a triode Q1, a voltage comparator U1, a voltage comparator U2 and a light-emitting diode D1, an emitting electrode of the triode Q1 is grounded, a collector electrode of the triode Q1 is connected with an inverted input end of the voltage comparator U1, a power supply is connected with an anode of a diode D2, and a cathode of the diode D2 is connected with an anode of the charging IC. The cathode of the diode D2 is connected with the normal phase input end of the voltage comparator U1, the inverted phase input end of the voltage comparator U1, the anode of the light emitting diode D1 and the normal phase input end of the voltage comparator U2, and the output end of the voltage comparator U1 is connected with the inverted phase input end of the voltage comparator U2. The output end of the voltage comparator U2 is connected with the cathode of a diode D3, the anode of the diode D3 is connected with the anode of a light emitting diode D1, and the cathode of the light emitting diode D1 is grounded. State change of the charging indicating lamp can be realized, cost is low, and fault probability is low.

Description

Technical Field

[0001] The utility model relates to a charging circuit, in particular to an auxiliary indicating circuit matched with a charging IC. Background Art

[0002] In order to save costs, many current charging ICs only have one light for charging indication. The light is on when charging is in progress, and off when fully charged. The status of the indicator light is rigid and cannot fully meet customer requirements. The status of the indicator light can be controlled by adding a single-chip microcomputer, but adding a single-chip microcomputer increases the cost and the probability of failure. Summary of the invention

[0003] The technical problem to be solved by the utility model is to provide an auxiliary indicating circuit matched with a charging IC, which can realize the state change of a charging indicator light, has low cost and low failure probability.

[0004] In order to solve the above technical problems, the technical solution of the utility model is: an auxiliary indication circuit for a charging IC, comprising a transistor Q1, a voltage comparator U1, a voltage comparator U2 and a light emitting diode D1, the emitter of the transistor Q1 is grounded, the collector of the transistor Q1 is connected to the inverting input terminal of the voltage comparator U1, the power supply is connected to the anode of the diode D2, the cathode of the diode D2 is respectively connected to the positive input terminal of the voltage comparator U1, the inverting input terminal of the voltage comparator U1, the anode of the light emitting diode D1 and the positive input terminal of the voltage comparator U2, the output terminal of the voltage comparator U1 is connected to the inverting input terminal of the voltage comparator U2, the output terminal of the voltage comparator U2 is connected to the cathode of the diode D3, the anode of the diode D3 is connected to the anode of the light emitting diode D1, and the cathode of the light emitting diode D1 is grounded. The principle of the utility model is as follows: when charging, the transistor Q1 is turned on, the voltage at the third foot of the voltage comparator U1 is higher than the voltage at the second foot and outputs a high level, the seventh foot of the voltage comparator U2 outputs a level that varies from high to low, so that the light-emitting diode D1 flashes on and off, indicating that it is charging; when fully charged, the transistor Q1 is turned off, the voltage at the third foot of the voltage comparator U1 is equal to the voltage at the second foot and outputs a low level, the seventh foot of the voltage comparator U2 outputs a high level, and the light-emitting diode D2 is always on, indicating that it is fully charged.

[0005] As an improvement, the base of the transistor Q1 is connected to the voltage stabilizing diode D4.

[0006] As an improvement, the power supply is +22.5V.

[0007] As an improvement, the diode D2 is connected to the non-inverting input terminal of the voltage comparator U1 through the resistor R11, and the diode D2 is connected to the inverting input terminal of the voltage comparator U1 through the resistor R10.

[0008] As an improvement, the positive phase input terminal of the voltage comparator U2 is grounded through a resistor R13, the inverting input terminal of the voltage comparator U2 is grounded through a capacitor C05, the inverting input terminal of the voltage comparator U2 is connected to its output terminal through a resistor R14, the cathode of the diode D2 is connected to the positive phase input terminal of the voltage comparator U2 through a resistor R16, the cathode of the diode D2 is connected to the output terminal of the voltage comparator U2 through a resistor R12, and a resistor R15 is provided between the positive phase input terminal and the output terminal of the voltage comparator U2.

[0009] Compared with the prior art, the utility model has the following beneficial effects:

[0010] No single-chip microcomputer control is required. The use of hardware circuit design can realize the status change of the charging indicator light, with low cost and low probability of failure. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 This is the circuit schematic diagram of the utility model. DETAILED DESCRIPTION

[0012] The utility model will be further described below in conjunction with the accompanying drawings.

[0013] like Figure 1 As shown, an auxiliary indication circuit for a charging IC includes a transistor Q1, a voltage comparator U1, a voltage comparator U2 and a light emitting diode D1. The base of the transistor Q1 is connected to a voltage stabilizing diode D4, the emitter of the transistor Q1 is grounded, and the collector of the transistor Q1 is connected to the inverting input terminal of the voltage comparator U1. The power supply +22.5V is connected to the anode of the diode D2, the cathode of the diode D2 is connected to the positive input terminal of the voltage comparator U1 through a resistor R11, the cathode of the diode D2 is connected to the inverting input terminal of the voltage comparator U1 through a resistor R10, the cathode of the diode D2 is connected to the anode of the light emitting diode D1 through a resistor R17, the cathode of the diode D2 is connected to the 8th pin of the voltage comparator U1, the cathode of the diode D2 is connected to the positive input terminal of the voltage comparator U2 through a resistor R16, and the cathode of the diode D2 is connected to the output terminal of the voltage comparator U2 through a resistor R12. The positive phase input terminal of the voltage comparator U2 is grounded through a resistor R13, the negative phase input terminal of the voltage comparator U2 is grounded through a capacitor C05, the negative phase input terminal of the voltage comparator U2 is connected to its output terminal through a resistor R14, a resistor R15 is provided between the positive phase input terminal and the output terminal of the voltage comparator U2, the output terminal of the voltage comparator U2 is connected to the cathode of the diode D3, the anode of the diode D3 is connected to the anode of the light emitting diode D1, and the cathode of the light emitting diode D1 is grounded. The output terminal of the voltage comparator U1 is connected to the negative phase input terminal of the voltage comparator U2.

[0014] The principle of the utility model is as follows: when charging, the transistor Q1 is turned on, the voltage at the third foot of the voltage comparator U1 is higher than the voltage at the second foot and outputs a high level, the seventh foot of the voltage comparator U2 outputs a level that varies from high to low, so that the light-emitting diode D1 flashes on and off, indicating that it is charging; when fully charged, the transistor Q1 is turned off, the voltage at the third foot of the voltage comparator U1 is equal to the voltage at the second foot and outputs a low level, the seventh foot of the voltage comparator U2 outputs a high level, and the light-emitting diode D2 is always on, indicating that it is fully charged.

Claims

1. An auxiliary indication circuit for a charging IC, characterized in that: It includes a transistor Q1, a voltage comparator U1, a voltage comparator U2 and a light emitting diode D1, wherein the emitter of the transistor Q1 is grounded, the collector of the transistor Q1 is connected to the inverting input terminal of the voltage comparator U1, the power supply is connected to the anode of the diode D2, the cathode of the diode D2 is respectively connected to the non-inverting input terminal of the voltage comparator U1, the inverting input terminal of the voltage comparator U1, the anode of the light emitting diode D1 and the non-inverting input terminal of the voltage comparator U2, the output terminal of the voltage comparator U1 is connected to the inverting input terminal of the voltage comparator U2, the output terminal of the voltage comparator U2 is connected to the cathode of the diode D3, the anode of the diode D3 is connected to the anode of the light emitting diode D1, and the cathode of the light emitting diode D1 is grounded.

2. The auxiliary indication circuit for a charging IC according to claim 1, characterized in that: The base of the transistor Q1 is connected to the voltage stabilizing diode D4.

3. The auxiliary indication circuit for a charging IC according to claim 1, characterized in that: The power supply is +22.5V.

4. The auxiliary indication circuit for a charging IC according to claim 1, characterized in that: The diode D2 is connected to the non-inverting input terminal of the voltage comparator U1 through the resistor R11 , and the diode D2 is connected to the inverting input terminal of the voltage comparator U1 through the resistor R10 .

5. The auxiliary indication circuit for a charging IC according to claim 1, characterized in that: The positive phase input terminal of the voltage comparator U2 is grounded through a resistor R13, the negative phase input terminal of the voltage comparator U2 is grounded through a capacitor C05, the negative phase input terminal of the voltage comparator U2 is connected to its output terminal through a resistor R14, the cathode of the diode D2 is connected to the positive phase input terminal of the voltage comparator U2 through a resistor R16, the cathode of the diode D2 is connected to the output terminal of the voltage comparator U2 through a resistor R12, and a resistor R15 is provided between the positive phase input terminal and the output terminal of the voltage comparator U2.

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