CN202818268U

CN202818268U - Safe drive circuit

Info

Publication number: CN202818268U
Application number: CN201220467520.XU
Authority: CN
Inventors: 陈文超; 陈亚骏
Original assignee: SHANGHAI PROPHET ELECTRONIC TECHNOLOGY Co Ltd
Current assignee: SHANGHAI PROPHET ELECTRONIC TECHNOLOGY Co Ltd
Priority date: 2012-09-13
Filing date: 2012-09-13
Publication date: 2013-03-20
Anticipated expiration: 2022-09-13

Abstract

The utility model brings forward a safe drive circuit. The safe drive circuit comprises an optical coupler, a drive chip, a capacitor, an isolation transformer, a rectification circuit, a fuse and a diode. An output terminal of the optical coupler is connected with an input terminal of the drive chip. An output terminal of the drive chip is connected with an input terminal of the isolation transformer via the capacitor. An output terminal of the isolation transformer is connected with an input terminal of the rectification circuit. An output terminal of the rectification circuit is connected with the diode through the fuse. The beneficial effects are that the safe drive circuit is safe and reliable, and allows no wrong output on a non-safe side to occur if any device breaks down.

Description

A kind of safe driving circuit

Technical field

The utility model relates to drive circuit, refers to especially a kind of safe driving circuit.

Background technology

Drive circuit refers between main circuit and control circuit, is used for the intermediate circuit that signal to control circuit amplifies, and namely the signal of amplification control circuit can the driving power transistor.

The basic task of drive circuit, the signal that exactly the information electronic circuit is transmitted is converted to and is added between power electronic device control end and the common port signal that can make it open or turn-off according to the requirement of its control target.Traditional safe driving circuit adopts the level formula to drive, and is easy to cause the mistake output of hazardous side.

The utility model content

In order to address the above problem, the utility model provides a kind of safe driving circuit.A kind of safe driving circuit that the utility model provides, safety, reliable, wherein arbitrary device breaks down and also can not produce the situation of non-security side mistake output.

The technical solution of the utility model is achieved in that

A kind of safe driving circuit, comprise optocoupler, drive chip, electric capacity, isolating transformer, rectification circuit, fuse, diode, the output of described optocoupler is connected with the input that drives chip, the output of described driving chip is connected with the input of isolating transformer by electric capacity, the output of described isolating transformer is connected with the input of rectification circuit, and the output of described rectification circuit is connected with diode by fuse.

The safe driving circuit that the utility model provides is to be connected between main circuit and the control circuit, the intermediate circuit that the safety signal of control circuit is amplified, wherein

Optocoupler is in order to the pulse signal of return pulse signal and Isolation input, output;

Drive chip, in order to driving power to be provided;

Electric capacity is to isolate the direct current of described driving chip generation and protect transformer.

Above-mentioned a kind of safe driving circuit wherein, also comprises detection module, and the output of described rectification circuit is connected with detection module by fuse.Described detection module is in order to detect whether driven of described safe driving circuit.When driven is arranged, this end that fuse is connected with detection module is high level, and the optocoupler process is namely arranged, and detects the optocoupler conducting; If do not drive, this end that fuse is connected with detection module is low level, detects not conducting of optocoupler.Output to simultaneously control circuit, allow operating personnel whether learn driven by control circuit.A kind of safe driving circuit that the utility model provides, adopt the pulsed drive Modular circuit design, when drive source does not have driving pulse, detection module has but detected driving pulse, can learn in the circuit that wiring error or detection module circuit are out of order, can the alert notice maintenance or close electricity and guarantee safety; If drive source has driving pulse, detection module but detects without driving, and can learn that then drive circuit is out of order or detection module is out of order, thereby reports to the police or do not send out driving pulse.

A kind of safe driving circuit that the utility model provides, adopt the pulsed drive Modular circuit design, if drive source can't produce pulse or drive circuit breaks down, the relay of final track traffic signal equipment can not picked up by mistake and caused the mistake output of non-security side, and circuit is originally as internal type fail-safe circuit, therefore arbitrary device situation that also can not produce non-security side mistake output (correctly be " 0 ", be output as by mistake " 1 ") that breaks down wherein.

Description of drawings

In order to be illustrated more clearly in the utility model embodiment or technical scheme of the prior art, the below will do to introduce simply to the accompanying drawing of required use in embodiment or the description of the Prior Art, apparently, accompanying drawing in the following describes only is embodiment more of the present utility model, for those of ordinary skills, under the prerequisite of not paying creative work, can also obtain according to these accompanying drawings other accompanying drawing.

Fig. 1 is the theory diagram of a kind of safe driving circuit of the utility model.

Embodiment

Below in conjunction with the accompanying drawing among the utility model embodiment, the technical scheme among the utility model embodiment is clearly and completely described, obviously, described embodiment only is the utility model part embodiment, rather than whole embodiment.Based on the embodiment in the utility model, those of ordinary skills are not making the every other embodiment that obtains under the creative work prerequisite, all belong to the scope of the utility model protection.

As shown in Figure 1, a kind of safe driving circuit, comprise optocoupler 1, drive chip 2, electric capacity 3, isolating transformer 4, rectification circuit 5, fuse 6, diode 7, detection module 8, the output of described optocoupler 1 is connected with the input that drives chip 2, the output of described driving chip 2 is connected with the input of isolating transformer 4 by electric capacity 3, the output of described isolating transformer 4 is connected with the input of rectification circuit 5, the output of described rectification circuit 5 is connected with diode 7 by fuse 6, and the output of described rectification circuit 5 is connected with detection module 8 by fuse 7.

Above-mentioned a kind of safe driving circuit, wherein,

Optocoupler: input pulse is by external control, and the relay coil representative value that the driving terminal connects is 24V, therefore needs optocoupler to isolate;

Drive chip: inside is MOSFET Drivers principle, the input and output homophase, and truth table is as follows:

IN	OUT
		0	0
1	1

Electric capacity: stopping direct current, protection rear end transformer direct current output occurs because drive chip, easily burns transformer;

Isolating transformer: the main devices of pulsed drive generation effect, make that arbitrary device breaks down in the circuit, do not have pulse and produce system's failure to the safe side;

Detection module: whether this detection module can detect this drive circuit good, and the circuit of detection module also utilizes optocoupler realization high pressure and low pressure directly to isolate;

Fuse: burn circuit when preventing from driving the relay coil short circuit that terminal connects.

In the course of the work, safe driving circuit is to be connected between main circuit 10 and the control circuit 9, the output of diode 7 connects the relay in the main circuit 10, the outside driving control wave of initiating, drive chip 2 output pulses and arrive transformer 4 inputs through a capacitance 3, transformer 4 couplings by 1:1 output to back-end circuit, by giving the rectification circuit charge inside after rectification circuit 5 rectifications, thereby realize driving.When control signal sent permanent " height " or permanent " low ", this drive circuit was not worked, and relay does not pick up.

The above only is preferred embodiment of the present utility model; not in order to limit the utility model; all within spirit of the present utility model and principle, any modification of doing, be equal to replacement, improvement etc., all should be included within the protection range of the present utility model.

Claims

1. safe driving circuit, it is characterized in that, comprise optocoupler, drive chip, electric capacity, isolating transformer, rectification circuit, fuse, diode, the output of described optocoupler is connected with the input that drives chip, the output of described driving chip is connected with the input of isolating transformer by electric capacity, the output of described isolating transformer is connected with the input of rectification circuit, and the output of described rectification circuit is connected with diode by fuse.

2. a kind of safe driving circuit according to claim 1 is characterized in that, also comprises detection module, and the output of described rectification circuit is connected with detection module by fuse.