CN203243559U - Indication lamp circuit and adapter - Google Patents

Abstract

The utility model discloses an indicator light circuit and an adapter, wherein the indicator light circuit is used to control and indicate that the indicator light of the adapter is illuminated or extinguished, and is respectively connected with an AC power supply and a switching power supply of the adapter, including an indicator light, a photoelectric control module, a charger The discharge control module and the switch control module; the indicator light circuit of the present invention, when the adapter is powered on, the photoelectric control module takes power from the AC power supply, and controls the switch control module to conduct to drive the indicator light to emit light; when the adapter is powered off , the photoelectric control module does not work, the charge and discharge control module takes power from the switching power supply for charging, and the discharge control switch control module is disconnected to control the indicator light to go out, and the adapter can be controlled to power off by adjusting the charging time of the charge and discharge control module After the time when the indicator light goes out, the indicator light can be quickly extinguished after the adapter is powered off, and the problem of misjudgment caused by the delayed extinguishment of the indicator light can be solved.

Description

LED circuits and adapters

technical field

The utility model relates to the technical field of power supplies, in particular to an indicator lamp circuit and an adapter.

Background technique

Most electronic equipment and electrical appliances use alternating current as their power supply, and many electronic equipment and electrical appliances use adapters as power supplies for the sake of versatility. The current adapter requires that the no-load power consumption be as low as possible. Generally, the no-load power consumption of the adapter can be less than 0.5W, and the good adapter can be less than 100mW. However, this brings new problems, because the adapter LED lights are installed on the power supply to indicate the power output. When the adapter is powered off, because the filter capacitor of the internal power supply of the adapter has energy storage, and the no-load power consumption of the switching power supply is very small, the light will take a long time to go out. (Generally it takes more than 30 seconds, some even take more than 2 minutes), user feedback will cause misjudgment, mistakenly think that the adapter has not been powered off.

Utility model content

The main purpose of the utility model is to provide an indicator light circuit and an adapter, aiming at realizing that the indicator light is quickly extinguished after the adapter is powered off, and avoiding misjudgment caused by the delayed extinguishment of the indicator light.

In order to achieve the above object, the utility model proposes an indicator light circuit, which is used to control and indicate that the indicator light of the adapter is on or off, and is respectively connected with the AC power supply and the switching power supply of the adapter, including the indicator light, whose It is characterized in that the indicator light circuit further includes a switch control module for controlling the light on or off, and a photoelectric control module for controlling the light emission of the indicator light through the switch control module when the AC power supply is supplied. module, and includes a charging and discharging control module for controlling the indicator light to be extinguished through the switch control module and controlling the extinguishing time of the indicator light when the AC power supply is not powered; wherein,

The input terminal of the photoelectric control module is connected to the AC power supply, the output terminal of the photoelectric control module is connected to the control terminal of the switch control module; the input terminal of the charge and discharge control module is connected to the output of the switch power supply The output terminal of the charge and discharge control module is connected to the control terminal of the switch control module; the input terminal of the switch control module is connected to the output terminal of the switching power supply, and the output terminal of the switch control module is connected to the output terminal of the switch control module. The indicator lights are connected.

Preferably, the output terminal of the photoelectric control module is connected to the output terminal of the switching power supply through the charge and discharge control module, and the control terminal of the photoelectric control module is connected to the input terminal of the switching power supply; the switching power supply The input terminal of the switching power supply includes a positive input terminal and a negative input terminal, and the output terminal of the switching power supply includes a positive output terminal and a negative output terminal.

Preferably, the photoelectric control module includes a photocoupler, a first diode, a second diode and a first resistor, and the photocoupler includes a primary side light-emitting diode and a secondary side triode; the first two The anode of the pole tube is connected to the first input terminal of the AC power supply, the cathode of the first diode is connected to the anode of the primary side light-emitting diode via the first resistor; the anode of the second diode The anode is connected to the second input terminal of the AC power supply, and the cathode of the second diode is connected to the anode of the primary side light-emitting diode through the first resistor; the cathode of the primary side light-emitting diode is used as the The control terminal of the photoelectric control module is connected to the negative input terminal of the switching power supply, and the collector of the triode on the secondary side is used as the output terminal of the photoelectric control module to be connected to the switching control module. The emitter of the triode is connected with the negative output terminal of the switching power supply.

Preferably, the charging and discharging control module includes a capacitor and a second resistor; one end of the capacitor is connected to the positive output end of the switching power supply via the second resistor, and the other end of the capacitor is connected to the positive output end of the switching power supply. The negative output terminal of the second resistor and the capacitor are connected to the control terminal of the switch control module as the output terminal of the charge and discharge control module.

Preferably, the switch control module includes a first switch element and a second switch element; the first switch element is connected to the collector of the secondary side triode of the photocoupler, and is connected to the switching power supply, the The charging and discharging control module is connected to the second switching element, and the second switching element is connected to the switching power supply and to the indicator light.

Preferably, the first switching element is a first triode, and the second switching element is a second triode; the base of the first triode is connected to the second resistor and the capacitor The common end is connected, and is connected with the collector of the secondary side triode of the photocoupler, and the collector of the first triode is connected with the positive output terminal of the switching power supply, and is connected with the second triode The base of the transistor is connected, the emitter of the first triode is connected with the negative output terminal of the switching power supply; the collector of the second triode is connected with the positive output terminal of the switching power supply, and the The emitter of the second triode is connected with the indicator light.

Preferably, the switch control module further includes a third resistor and a fourth resistor, and the indicator light includes a light emitting diode; one end of the third resistor is used as an input end of the switch control module, and is connected to the positive end of the switching power supply. The other end of the third resistor is connected to the collector of the first transistor and the base of the second transistor respectively; the fourth resistor is connected to the second transistor Between the emitter of the tube and the anode of the light emitting diode, the cathode of the light emitting diode is connected to the negative output terminal of the switching power supply.

Preferably, the first switch element is a first MOS transistor, and the second switch element is a second MOS transistor; the gate of the first MOS transistor is connected to the common end of the second resistor and the capacitor , and is connected to the collector of the secondary side triode of the photocoupler, the drain of the first MOS transistor is connected to the positive output terminal of the switching power supply, and is connected to the gate of the second MOS transistor , the source of the first MOS transistor is connected to the negative output terminal of the switching power supply; the drain of the second MOS transistor is connected to the positive output terminal of the switching power supply, and the source of the second MOS transistor Connect with said indicator light.

Preferably, the switch control module further includes a third resistor and a fourth resistor, and the indicator light includes a light emitting diode; one end of the third resistor is used as an input end of the switch control module, and is connected to the positive end of the switching power supply. The other end of the third resistor is connected to the drain of the first MOS transistor and the gate of the second MOS transistor respectively; the fourth resistor is connected to the source of the second MOS transistor between the pole and the anode of the light emitting diode, and the cathode of the light emitting diode is connected to the negative output terminal of the switching power supply.

The utility model also proposes an adapter, which includes an AC power supply, a rectification filter circuit and a switching power supply, and also includes an indicator light circuit, the indicator light circuit is respectively connected with the AC power supply and the switching power supply, and the rectification filter circuit The circuit is connected between the AC power supply and the switching power supply; the indicator light circuit is used to control and indicate that the indicator light of the adapter is on or off, the indicator light circuit includes the indicator light, and the indicator light circuit also It includes a switch control module for controlling the light on or off, a photoelectric control module for controlling the light to light through the switch control module when the AC power supply is powered, and a photoelectric control module for When the AC power supply is not supplied, the charging and discharging control module controls the extinguishing of the indicator light through the switch control module and controls the extinguishing time of the indicator light; wherein,

The input terminal of the photoelectric control module is connected to the AC power supply, the output terminal of the photoelectric control module is connected to the control terminal of the switch control module; the input terminal of the charge and discharge control module is connected to the switch power supply, The output terminal of the charge and discharge control module is connected to the control terminal of the switch control module; the input terminal of the switch control module is connected to the switching power supply, and the output terminal of the switch control module is connected to the indicator light.

The indicator light circuit proposed by the utility model, when the AC power supply is supplied, that is, when the adapter is energized, the photoelectric control module takes power from the AC power supply, and controls the switch control module to conduct, and the switch control module drives the indicator light to emit light; when the AC power supply does not supply power , that is, when the adapter cuts off the AC input, the photoelectric control module does not work, and the charging and discharging control module takes power from the switching power supply to charge and store electric energy. When the stored electric energy is enough to control the switch control module to be disconnected, the control switch control module is disconnected , the switch control module controls the indicator light to go out, and the extinguishing time of the indicator light can be controlled by adjusting the charging time of the charging and discharging control module, that is, the time from when the adapter is powered off to when the indicator light is extinguished can be shortened by adjusting the charging time The time from when the adapter is powered off to when the indicator light goes out, so that the indicator light can be quickly turned off after the adapter is powered off, and avoid misjudgment of whether the adapter is powered off or not. Compared with the prior art, the indicator light circuit of the utility model achieves the purpose of quickly extinguishing the indicator light after the adapter is powered off by adjusting and shortening the extinguishing time of the indicator light without increasing the power consumption of the adapter, and solves the problems caused by the indicator light. The problem of misjudgment caused by delayed extinguishing.

Description of drawings

Fig. 1 is the functional block diagram of the preferred embodiment of the indicator light circuit of the present invention;

Fig. 2 is a circuit structure schematic diagram of an embodiment of the indicator light circuit of the present invention;

FIG. 3 is a schematic diagram of the circuit structure of another embodiment of the indicator light circuit of the present invention.

The realization of the purpose, functional characteristics and advantages of the utility model will be further described in conjunction with the embodiments and with reference to the accompanying drawings.

Detailed ways

The technical solution of the utility model is further described below in conjunction with the accompanying drawings and specific embodiments of the description. It should be understood that the specific embodiments described here are only used to explain the utility model, and are not intended to limit the utility model.

The utility model provides an indicator light circuit.

Referring to FIG. 1 , FIG. 1 is a functional block diagram of a preferred embodiment of the indicator light circuit 400 of the present invention.

In the embodiment of the present utility model, the indicator light circuit 400 is used to control and indicate that the indicator light 410 of the adapter is illuminated or extinguished, and is respectively connected with the AC power supply 100 and the switching power supply 300 of the adapter. The indicator light circuit 400 includes an indicator light 410, a photoelectric control module 420, the charge and discharge control module 430 and the switch control module 440; the switch control module 440 is used to control the light 410 to light up or go out, and the photoelectric control module 420 is used to control the light 410 to light up through the switch control module 440 when the AC power supply 100 supplies power The charging and discharging control module 430 is used to control the indicator light 410 to turn off through the switch control module 440 when the AC power supply 100 is not supplying power, and to control the time for turning off the indicator light 410 .

Wherein, the input terminal of the photoelectric control module 420 is connected with the AC power supply 100, the output terminal of the photoelectric control module 420 is connected with the control terminal of the switch control module 440; The output terminal of the discharge control module 430 is connected to the control terminal of the switch control module 440 ;

The indicator light circuit 400 proposed by the utility model, when the AC power supply 100 supplies power and the instant adapter is powered on, the photoelectric control module 420 takes power from the AC power supply 100, and controls the switch control module 440 to conduct, and the switch control module 440 drives the indicator light 410 Lighting; when the AC power supply 100 does not supply power, that is, when the adapter is powered off, the photoelectric control module 420 does not work, and the charge and discharge control module 430 takes power from the switching power supply 300 to charge and store electric energy. When the stored electric energy is sufficient to control the switch control module 440 to turn off When on, the control switch control module 440 is disconnected, the switch control module 440 controls the indicator light 410 to go out, and the extinguishing time of the indicator light 410 can be controlled by adjusting the charging time of the charge and discharge control module 430, that is, the adapter can be controlled to be powered off. The time when the indicator light 410 goes out, therefore, the time from when the adapter is powered off to when the indicator light 410 is turned off can be shortened by adjusting the charging time, so that the indicator light 410 can be quickly turned off after the adapter is powered off, and avoid misunderstanding whether the adapter is powered off or not. judge.

Compared with the prior art, the indicator light circuit 400 of the present invention shortens the extinguishing time of the indicator light 410 by adjusting and shortening the extinguishing time of the indicator light 410 without increasing the power consumption of the adapter, so as to achieve the purpose of quickly extinguishing the indicator light 410 after the adapter is powered off, and solve the problem caused by the indicator light. The delay of 410 is turned off, which leads to the problem of misjudgment.

Referring to FIG. 1 and FIG. 2 together, FIG. 2 is a schematic circuit structure diagram of an embodiment of the indicator light circuit 400 of the present invention.

In this embodiment, the output terminal of the photoelectric control module 420 is connected to the output terminal of the switching power supply 300 through the charge and discharge control module 430, and the control terminal of the photoelectric control module 420 is connected to the input terminal of the switching power supply 300; the input terminal of the switching power supply 300 includes The positive input terminal VI+ and the negative input terminal VI-, the output terminal of the switching power supply 300 includes a positive output terminal VO+ and a negative output terminal VO-.

In this embodiment, the photoelectric control module 420 includes a photocoupler U1, a first diode D1, a second diode D2, and a first resistor R1, and the photocoupler U1 includes a primary-side light-emitting diode U1A and a secondary-side transistor U1B. The anode of the first diode D1 is connected to the first input terminal AC1 of the AC power supply 100, and the cathode of the first diode D1 is connected to the anode of the primary side light-emitting diode U1A of the photocoupler U1 via the first resistor R1; The anode of the second diode D2 is connected to the second input terminal AC2 of the AC power supply 100, and the cathode of the second diode D2 is connected to the anode of the primary side light-emitting diode U1A of the photocoupler U1 via the first resistor R1; The cathode of the primary side light-emitting diode U1A of U1 is used as the control terminal of the photoelectric control module 420, and is connected to the negative input terminal VI- of the switching power supply 300. When the primary side light-emitting diode U1A emits light, it controls the secondary side transistor U1B to turn on, and the primary side emits light. When the diode U1A is not emitting light, control the secondary transistor U1B to cut off, the collector of the secondary transistor U1B of the photocoupler U1 is connected to the input terminal of the switch control module 440, and the emitter of the secondary transistor U1B of the photocoupler U1 It is connected with the negative output terminal VO- of the switching power supply 300 .

In this embodiment, the charging and discharging control module 430 includes a capacitor C1 and a second resistor R2; one end of the capacitor C1 is connected to the positive output terminal VO+ of the switching power supply 300 through the second resistor R2, and the other end of the capacitor C1 is connected to the negative output terminal of the switching power supply 300. The output terminal VO- is connected; the common terminal of the second resistor R2 and the capacitor C1 is used as the output terminal of the charge and discharge control module 430 and is connected to the control terminal of the switch control module 440 .

In this embodiment, the switch control module 440 includes a first switch element 441 and a second switch element 442; the first switch element 441 is connected to the collector of the secondary side transistor U1B of the photocoupler U1, and the first switch element 441 is respectively It is connected with the switching power supply 300 , the charging and discharging control module 430 and the second switching element 442 , the second switching element 442 is connected with the switching power supply 300 , and the second switching element 442 is connected with the indicator light 410 .

Specifically, the first switch element 441 is a first transistor Q11, and the second switch element 442 is a second transistor Q12. In this embodiment, both the first transistor Q11 and the second transistor Q12 are NPN type transistor. The base of the first transistor Q11 is connected to the common end of the second resistor R2 and the capacitor C1, and the base of the first transistor Q11 is connected to the collector of the secondary side transistor U1B of the photocoupler U1, and the first The collector of the transistor Q11 is connected to the positive output terminal VO+ of the switching power supply 300, and the base of the first transistor Q11 is connected to the base of the second transistor Q12, and the emitter of the first transistor Q11 is connected to the base of the second transistor Q11. The negative output terminal VO- of the switching power supply 300 is connected; the collector of the second transistor Q12 is connected to the positive output terminal VO+ of the switching power supply 300 , and the emitter of the second transistor Q12 is connected to the indicator light 410 .

Specifically, the switch control module 440 also includes a third resistor R3 and a fourth resistor R4, and the indicator light 410 includes a light-emitting diode LED; one end of the third resistor R3 is used as the input terminal of the switch control module 440, and is connected to the positive output terminal of the switching power supply 300 VO+ connection, the other end of the third resistor R3 is respectively connected to the collector of the first transistor Q11 and the base of the second transistor Q12; the fourth resistor R4 is connected to the emitter of the second transistor Q12 and the light emitting Between the anodes of the LEDs, the cathodes of the LEDs are connected to the negative output terminal VO− of the switching power supply 300 .

The working principle of the indicator light circuit 400 shown in FIG. 2 is specifically described as follows:

When the AC power supply 100 supplies power and the instant adapter is powered on, the primary side light-emitting diode U1A of the photocoupler U1 obtains power from the AC power input by the AC power supply 100 through the first diode D1, the second diode D2 and the first resistor R1, Since the primary-side light-emitting diode U1A of the photocoupler U1 has high sensitivity, the power consumption of the primary-side light-emitting diode U1A of the photocoupler U1 from AC power is negligible. At the same time, since the primary side light-emitting diode U1A of the photocoupler U1 is powered, the secondary side transistor U1B of the photocoupler U1 is turned on. Therefore, the BE junction of the first transistor Q11 is short-circuited by the secondary side transistor U1B of the photocoupler U1, and the first transistor Q11 is not conducted. And because the voltage output by the positive output terminal VO+ of the switching power supply 300 is added to the base of the second transistor Q12 through the third resistor R3, the second transistor Q12 is turned on, so the output voltage of the positive output terminal VO+ of the switching power supply 300 is The voltage is applied to the anode of the light-emitting diode LED through the second transistor Q12 and the fourth resistor R4, the light-emitting diode LED emits light, and the light-emitting diode LED indicates that the adapter has power, indicating that the adapter has not been powered off.

When the AC power supply 100 does not supply power, that is, when the adapter is powered off, the primary side light-emitting diode U1A of the photocoupler U1 has no current flowing and does not emit light, the secondary side transistor U1B of the photocoupler U1 is cut off, and the photocoupler U1 does not work. The voltage output by the positive output terminal VO+ of the switching power supply 300 charges the capacitor C1 through the second resistor R2. When the voltage generated on the capacitor C1 is sufficient to drive the first transistor Q11 to conduct, the capacitor C1 charges the first transistor Q11. Discharge, the first transistor Q11 is turned on, thereby pulling down the base potential of the second transistor Q12, the second transistor Q12 is cut off, the light-emitting diode LED loses power supply and goes out, and the light-emitting diode LED indicates that the adapter has been powered off . Since this embodiment can adjust the charging time of the charging and discharging control module 430 by selecting the resistance value of the second resistor R2 and the capacitance of the capacitor C1, and then can control the time from when the adapter is not connected to the AC power to when the light-emitting diode LED goes out, Therefore, by adjusting the charging time of the charging and discharging control module 430, it is very convenient to control the time from when the adapter is powered off to when the light-emitting diode LED is extinguished, and appropriately shorten the extinguishing time of the light-emitting diode LED according to actual needs, so that the light-emitting diode LED can be realized after the adapter is powered off. The LED, that is, the indicator light of the adapter, goes out quickly, indicating that the adapter has been powered off, so as to avoid misjudging whether the adapter is powered off or not.

Referring to FIG. 1 and FIG. 3 , FIG. 3 is a schematic diagram of the circuit structure of another embodiment of the indicator light circuit 400 of the present invention.

In this embodiment, the photoelectric control module 420 includes a photocoupler U1, a first diode D1, a second diode D2, and a first resistor R1, and the photocoupler U1 includes a primary-side light-emitting diode U1A and a secondary-side transistor U1B. The anode of the first diode D1 is connected to the first input terminal AC1 of the AC power supply 100, and the cathode of the first diode D1 is connected to the anode of the primary side light-emitting diode U1A of the photocoupler U1 via the first resistor R1; The anode of the second diode D2 is connected to the second input terminal AC2 of the AC power supply 100, and the cathode of the second diode D2 is connected to the anode of the primary side light-emitting diode U1A of the photocoupler U1 via the first resistor R1; The cathode of the primary side light-emitting diode U1A of U1 is used as the control terminal of the photoelectric control module 420, and is connected to the negative input terminal VI- of the switching power supply 300. When the primary side light-emitting diode U1A emits light, it controls the secondary side transistor U1B to turn on, and the primary side emits light. When the diode U1A is not emitting light, control the secondary transistor U1B to cut off, the collector of the secondary transistor U1B of the photocoupler U1 is connected to the input terminal of the switch control module 440, and the emitter of the secondary transistor U1B of the photocoupler U1 It is connected with the negative output terminal VO- of the switching power supply 300 .

In this embodiment, the charging and discharging control module 430 includes a capacitor C1 and a second resistor R2; one end of the capacitor C1 is connected to the positive output terminal VO+ of the switching power supply 300 through the second resistor R2, and the other end of the capacitor C1 is connected to the negative output terminal of the switching power supply 300. The output terminal VO- is connected; the common terminal of the second resistor R2 and the capacitor C1 is used as the output terminal of the charge and discharge control module 430 and is connected to the control terminal of the switch control module 440 .

In this embodiment, the switch control module 440 includes a first switch element 441 and a second switch element 442; the first switch element 441 is connected to the collector of the secondary side transistor U1B of the photocoupler U1, and the first switch element 441 is respectively It is connected with the switching power supply 300 , the charging and discharging control module 430 and the second switching element 442 , the second switching element 442 is connected with the switching power supply 300 , and the second switching element 442 is connected with the indicator light 410 .

Specifically, the first switch element 441 is a first MOS transistor Q21, and the second switch element 442 is a second MOS transistor Q22. In this embodiment, both the first MOS transistor Q21 and the second MOS transistor Q22 are NMOS transistors; The gate of a MOS transistor Q21 is connected to the common end of the second resistor R2 and the capacitor C1, and the gate of the first MOS transistor Q21 is connected to the collector of the secondary side transistor U1B of the photocoupler U1, and the first MOS transistor Q21 The drain of the first MOS transistor Q21 is connected to the positive output terminal VO+ of the switching power supply 300, and the drain of the first MOS transistor Q21 is connected to the gate of the second MOS transistor Q22, and the source of the first MOS transistor Q21 is connected to the negative output terminal of the switching power supply 300 VO- connection; the drain of the second MOS transistor Q22 is connected to the positive output terminal VO+ of the switching power supply 300 , and the source of the second MOS transistor Q22 is connected to the indicator light 410 .

Specifically, the switch control module 440 also includes a third resistor R3 and a fourth resistor R4, and the indicator light 410 includes a light-emitting diode LED; one end of the third resistor R3 is used as the input terminal of the switch control module 440, and is connected to the positive output terminal of the switching power supply 300 VO+ connection, the other end of the third resistor R3 is respectively connected to the drain of the first MOS transistor Q21 and the gate of the second MOS transistor Q22; the fourth resistor R4 is connected to the source of the second MOS transistor Q22 and the light emitting diode LED Between the anodes, the cathode of the LED is connected to the negative output terminal VO- of the switching power supply 300 .

The working principle of the indicator light circuit 400 shown in FIG. 3 is specifically described as follows:

When the AC power supply 100 supplies power and the instant adapter is powered on, the primary side light-emitting diode U1A of the photocoupler U1 obtains power from the AC power input by the AC power supply 100 through the first diode D1, the second diode D2 and the first resistor R1, Since the primary-side light-emitting diode U1A of the photocoupler U1 has high sensitivity, the power consumption of the primary-side light-emitting diode U1A of the photocoupler U1 from AC power is negligible. At the same time, since the primary side light-emitting diode U1A of the photocoupler U1 is powered, the secondary side triode U1B of the photocoupler U1 is turned on. Therefore, the gate-source of the first MOS transistor Q21 is short-circuited by the secondary transistor U1B of the photocoupler U1, and the first MOS transistor Q21 is not turned on. And because the voltage output by the positive output terminal VO+ of the switching power supply 300 is added to the gate of the second MOS transistor Q22 through the third resistor R3, the second MOS transistor Q22 is turned on, so the voltage output by the positive output terminal VO+ of the switching power supply 300 passes through The second MOS transistor Q22 and the fourth resistor R4 are connected to the anode of the light-emitting diode LED, the light-emitting diode LED emits light, and the light-emitting diode LED indicates that the adapter has power, indicating that the adapter has not been powered off.

When the AC power supply 100 does not supply power, that is, when the adapter is powered off, the photodiode U1A on the primary side of the photocoupler U1 has no current flowing and does not emit light, the secondary side transistor U1B of the photocoupler U1 is cut off, and the photocoupler U1 does not work. The voltage output by the positive output terminal VO+ of the switching power supply 300 charges the capacitor C1 through the second resistor R2, and when the voltage generated on the capacitor C1 is sufficient to drive the first MOS transistor Q21 to conduct, the capacitor C1 discharges to the first MOS transistor Q21, The first MOS transistor Q21 is turned on, so that the gate potential of the second MOS transistor Q22 is pulled down, the second MOS transistor Q22 is turned off, the light-emitting diode LED loses power and goes out, and the light-emitting diode LED indicates that the adapter is powered off. Since this embodiment can adjust the charging time of the charging and discharging control module 430 by selecting the resistance value of the second resistor R2 and the capacitance of the capacitor C1, and then can control the time from when the adapter is not connected to the AC power to when the light-emitting diode LED goes out, Therefore, by adjusting the charging time of the charge-discharge control module 430, it is convenient to control the time from when the adapter is powered off to when the light-emitting diode LED is turned off, and appropriately shorten the time to turn off the light-emitting diode LED according to actual needs, so that the light-emitting diode LED can be realized after the adapter is powered off. The LED, that is, the indicator light of the adapter, goes out quickly, indicating that the adapter has been powered off, so as to avoid misjudging whether the adapter is powered off or not.

Compared with the prior art, the indicator lamp circuit 400 proposed by the utility model adjusts the charging time through the capacitor C1 and the second resistor R2 in the charge and discharge control module 430, so as to control the time from when the adapter is powered off to when the indicator lamp 410 goes out. The indicator light 410 can be quickly extinguished after the adapter is powered off, and the purpose of quickly extinguishing the indicator light 410 after the adapter is powered off is achieved without increasing the power consumption of the adapter. question.

The utility model also proposes an adapter, which includes an AC power supply 100, a rectifying and filtering circuit 200, a switching power supply 300 and an indicator light circuit 400. Between the AC power supply 100 and the switching power supply 300 , the circuit structure, working principle and beneficial effects of the indicator light circuit 400 refer to the above-mentioned embodiments, and will not be repeated here.

The above descriptions are only preferred embodiments of the present utility model, and are not therefore limiting the patent scope of the present utility model. Any equivalent structure or equivalent process transformation made by using the specification of the utility model and the contents of the accompanying drawings may be directly or indirectly used in Other relevant technical fields are all included in the patent protection scope of the present utility model in the same way.

Claims (10)

1. An indicator light circuit is used for controlling and indicating an indicator light of an adapter to emit light or extinguish, is respectively connected with an alternating current power supply and a switch power supply of the adapter, and comprises the indicator light; wherein,

the input end of the photoelectric control module is connected with the alternating current power supply, and the output end of the photoelectric control module is connected with the control end of the switch control module; the input end of the charge and discharge control module is connected with the output end of the switching power supply, and the output end of the charge and discharge control module is connected with the control end of the switching control module; the input end of the switch control module is connected with the output end of the switch power supply, and the output end of the switch control module is connected with the indicator lamp.

2. The indicator light circuit according to claim 1, wherein an output end of the photoelectric control module is connected with an output end of the switching power supply through the charge-discharge control module, and a control end of the photoelectric control module is connected with an input end of the switching power supply; the input end of the switching power supply comprises a positive input end and a negative input end, and the output end of the switching power supply comprises a positive output end and a negative output end.

3. The indicator light circuit according to claim 2, wherein the optoelectronic control module comprises an optocoupler, a first diode, a second diode, and a first resistor, the optocoupler comprising a primary side light emitting diode and a secondary side triode; the anode of the first diode is connected with the first input end of the alternating current power supply, and the cathode of the first diode is connected with the anode of the primary side light-emitting diode through the first resistor; the anode of the second diode is connected with the second input end of the alternating current power supply, and the cathode of the second diode is connected with the anode of the primary side light-emitting diode through the first resistor; the cathode of the primary side light emitting diode is used as the control end of the photoelectric control module and is connected with the negative input end of the switching power supply, the collector of the secondary side triode is used as the output end of the photoelectric control module and is connected with the switching control module, and the emitter of the secondary side triode is connected with the negative output end of the switching power supply.

4. The indicator light circuit according to claim 3, wherein the charge and discharge control module comprises a capacitor and a second resistor; one end of the capacitor is connected with the positive output end of the switching power supply through the second resistor, and the other end of the capacitor is connected with the negative output end of the switching power supply; and the common end of the second resistor and the capacitor is used as the output end of the charge and discharge control module and is connected with the control end of the switch control module.

5. The indicator light circuit according to claim 4, wherein the switch control module comprises a first switching element and a second switching element; the first switch element is connected with a collector of a secondary triode of the photoelectric coupler and respectively connected with the switching power supply, the charge and discharge control module and the second switch element, and the second switch element is connected with the switching power supply and the indicator light.

6. The indicator light circuit according to claim 5, wherein the first switching element is a first transistor and the second switching element is a second transistor; the base electrode of the first triode is connected with the common end of the second resistor and the capacitor and is connected with the collector electrode of the secondary triode of the photoelectric coupler, the collector electrode of the first triode is connected with the positive output end of the switching power supply and is connected with the base electrode of the second triode, and the emitter electrode of the first triode is connected with the negative output end of the switching power supply; and the collector of the second triode is connected with the positive output end of the switching power supply, and the emitter of the second triode is connected with the indicator light.

7. The indicator light circuit of claim 6, wherein the switch control module further comprises a third resistor and a fourth resistor, the indicator light comprising a light emitting diode; one end of the third resistor is used as the input end of the switch control module and is connected with the positive output end of the switch power supply, and the other end of the third resistor is respectively connected with the collector electrode of the first triode and the base electrode of the second triode; the fourth resistor is connected between the emitting electrode of the second triode and the anode of the light-emitting diode, and the cathode of the light-emitting diode is connected with the negative output end of the switching power supply.

8. The indicator light circuit according to claim 5, wherein the first switching element is a first MOS transistor, and the second switching element is a second MOS transistor; the grid electrode of the first MOS tube is connected with the common end of the second resistor and the capacitor and is connected with the collector electrode of a secondary triode of the photoelectric coupler, the drain electrode of the first MOS tube is connected with the positive output end of the switching power supply and is connected with the grid electrode of the second MOS tube, and the source electrode of the first MOS tube is connected with the negative output end of the switching power supply; the drain electrode of the second MOS tube is connected with the positive output end of the switching power supply, and the source electrode of the second MOS tube is connected with the indicator lamp.

9. The indicator light circuit of claim 8, wherein the switch control module further comprises a third resistor and a fourth resistor, the indicator light comprising a light emitting diode; one end of the third resistor is used as the input end of the switch control module and is connected with the positive output end of the switch power supply, and the other end of the third resistor is respectively connected with the drain electrode of the first MOS tube and the grid electrode of the second MOS tube; the fourth resistor is connected between the source electrode of the second MOS tube and the anode of the light-emitting diode, and the cathode of the light-emitting diode is connected with the negative output end of the switching power supply.

10. An adapter, comprising an ac power supply, a rectifying and filtering circuit and a switching power supply, characterized by further comprising an indicator light circuit according to any one of claims 1 to 9, the indicator light circuit being connected to the ac power supply and the switching power supply, respectively, the rectifying and filtering circuit being connected between the ac power supply and the switching power supply.

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