CN217824400U

CN217824400U - Circuit for improving emergency power supply switching speed

Info

Publication number: CN217824400U
Application number: CN202220513776.3U
Authority: CN
Inventors: 庄彪麟; 周正国
Original assignee: SHANGHAI ARCATA ELECTRONIC Inc; Crawford Global Ltd
Current assignee: SHANGHAI ARCATA ELECTRONIC Inc; Crawford Global Ltd
Priority date: 2022-03-10
Filing date: 2022-03-10
Publication date: 2022-11-15
Anticipated expiration: 2032-03-10

Abstract

The utility model provides an improve emergency power source switching speed's circuit. The circuit comprises a main board circuit and an auxiliary board circuit, wherein a triode is arranged, a base electrode is connected with an input commercial power of a rectifier bridge power supply through a divider resistor and a diode, the output of a collector electrode of the triode is connected with the base electrode of the other triode through a resistor, the collector electrode of the triode is connected with an FB pin of a main board circuit U2, and an emitting electrode of the triode is grounded. Once the mains supply is powered off, the triode Q2 is conducted, the potential of the FB pin of the U2 is pulled to the ground, the U2 is in an open-circuit protection mode, a processor of the auxiliary board circuit judges that the switching mode is achieved, and the switching mode is controlled to output a switching signal and switch the working mode. The utility model has the advantages that, it is few to use electron device, and equipment is small, simple to operate. In particular, the circuit switching speed is high, no delay time exists, and the working mode of the power supply can be switched instantly.

Description

Circuit for improving emergency power supply switching speed

Technical Field

The utility model belongs to the technical field of the LED lighting technology and specifically relates to LED drive power supply technical field.

Background

With the development of LED lighting technology and the wider application range, the requirement for response speed is higher and higher, especially for emergency lighting lamps and lamps with multiple power supplies. For example, under the condition that the LED lamp normally illuminates at night, the emergency lamp needs to be quickly switched to illuminate when the commercial power is suddenly cut off.

In the prior art, referring to fig. 3 and 4, when the commercial power is normally supplied, the main board circuit U2 operates to start the transformer T2 to charge the positive and negative electrodes of the battery BAT, the pin 7 CV of the processor MCU (XU 2 in fig. 4) of the sub board circuit is at a high level, and the processor MCU determines that the processor MCU is in a non-switching state.

Once the mains supply is powered off, the large electrolytic capacitor C1 discharges slowly, the main board circuit U2 stops working after continuously working for a period of time, then the T2 stops working, the CV is in a low level, the processor MCU judges that the switching state is achieved, and the 13-pin PWM2 outputs a control signal to switch a 5-pin starting working mode of the main board circuit U3 to a battery power supply mode.

The disadvantage is that the working mode switching is delayed for a period of time and the working mode cannot be switched quickly.

Disclosure of Invention

For making current LED drive power supply mode can fast switch over, the utility model provides an improve emergency power supply switching speed's circuit. The circuit comprises a main board circuit and an auxiliary board circuit, and is characterized in that a triode is arranged, a base electrode of the triode is connected with an input commercial power of a rectifier bridge power supply through a divider resistor and a diode, the output of a collector electrode of the triode is connected with the base electrode of the other triode through a resistor, the collector electrode of the triode is connected with an FB pin of a main board circuit U2, and an emitting electrode of the triode is grounded.

The utility model has the advantages that, it is few to use electron device, and equipment is small, simple to operate. Particularly, the circuit switching speed is high, no delay time exists, and the working mode of the power supply can be switched instantly.

Drawings

FIG. 1 is a schematic circuit of the present invention;

FIG. 2 is a fast switching circuit connected to a motherboard circuit according to the present invention;

FIG. 3 is a prior art motherboard circuit;

fig. 4 is a prior art sub-board circuit.

Detailed Description

Please refer to fig. 1, 2, 4, fig. 3 and 4 are the switching circuit of the existing working mode, the utility model discloses add fast switching circuit on the existing mainboard circuit (fig. 3), by triode Q1, the base passes through divider resistance R1 and R2, diode D1 is connected with the input commercial power L/N of rectifier bridge power, triode Q1 collecting electrode output is connected with another triode Q2 base through a resistance R4, this triode Q2 collecting electrode is connected with mainboard circuit U2's 3 feet FB, the projecting pole ground connection.

When the commercial power is normally supplied, Q1 is conducted, Q2 is cut off, and FB is at a high level. The main board circuit U2 works normally, the transformer T2 works, CV is high level, and the processor XU2 of the auxiliary board circuit judges that the working state is not switched.

Once the mains supply is powered off, the triode Q1 is cut off, the triode Q2 is conducted, the FB pin potential of the U2 of the main board circuit is pulled to the ground, the U2 is in an open circuit protection mode, output is stopped, the transformer T2 does not work, CV is low level, the processor XU2 judges that the switching state is achieved, and the pin 13 of the processor outputs a control signal PWM2 to enable the pin 5 starting working mode of the main board circuit U3 to be switched to the battery power supply mode.

Claims

1. The utility model provides an improve emergency power source switching speed's circuit, includes mainboard circuit and subplate circuit, its characterized in that sets up a triode, and the base passes through divider resistance, diode and rectifier bridge power's input commercial power is connected, and triode collecting electrode output is connected with another triode base through a resistance, and this triode collecting electrode is connected with mainboard circuit U2's FB foot, and the projecting pole ground connection.