CN113036736A

CN113036736A - Output circuit structure with overcurrent and overvoltage protection and self-checking functions

Info

Publication number: CN113036736A
Application number: CN201911252042.3A
Authority: CN
Inventors: 杨磊; 唐敏; 段敬琳
Original assignee: Shanghai Aviation Electric Co Ltd
Current assignee: Shanghai Aviation Electric Co Ltd
Priority date: 2019-12-09
Filing date: 2019-12-09
Publication date: 2021-06-25

Abstract

The invention discloses an output circuit structure with overcurrent and overvoltage protection and self-checking functions, which comprises an overcurrent and overvoltage protection module, a control module, a monitoring module, an output module and a processor module, wherein the overcurrent and overvoltage protection module is used for carrying out overvoltage and overcurrent protection on input and output voltages and outputting the voltages to the control module, the control module is used for controlling the voltage output by the overcurrent and overvoltage protection module according to a control signal output by the processor module, the monitoring module is used for outputting the output voltage of the control module to the processor module for BIT detection after processing, and the output module is used for outputting the output voltage of the control module after protection by an anti-reverse diode. The invention has the beneficial effects that: the overcurrent and overvoltage protection function of the output voltage of the product is realized, BIT detection is carried out on the output voltage, the reliability of the product is improved, the fault occurrence rate of the product is reduced, and the output voltage is effectively detected.

Description

Output circuit structure with overcurrent and overvoltage protection and self-checking functions

Technical Field

The invention relates to the field of voltage and current protection, in particular to an output circuit structure with overcurrent and overvoltage protection and self-checking functions.

Background

With the progress and development of science and technology, the requirements on the safety quality of power supply equipment on an airplane are higher and higher, and the requirements on monitoring and detection of the power supply equipment are also higher and higher. In the existing product, because the output voltage is not subjected to overcurrent and overvoltage protection design, and the harshness of the power supply environment on the airplane is added, the product is often burnt out due to overcurrent and overvoltage due to factors such as external short circuit or peak, the reliability of the product is reduced, and the product quality faces severe examination.

Disclosure of Invention

The invention aims to overcome the problems in the prior art and provides an output circuit structure with overcurrent and overvoltage protection and self-checking functions.

In order to achieve the purpose, the technical scheme of the invention is as follows: the utility model provides an output circuit structure with overcurrent and overvoltage protection and self-checking function includes, overcurrent and overvoltage protection module, control module, monitoring module, output module and processor module, overcurrent and overvoltage protection module is used for carrying out the excessive pressure and overcurrent protection and right to input and output voltage control module output voltage, control module is used for the basis processor module output control signal control the voltage output of overcurrent and overvoltage protection module output, monitoring module be used for with control module output voltage exports after handling for processor module carries out BIT and detects, output module is used for with control module's output voltage exports after protecting through preventing reverse diode.

As a preferred scheme of an output circuit structure with overcurrent and overvoltage protection and self-checking functions, the processor module is configured to output a control signal to the control module, collect a BIT detection signal of the monitoring module, and output a fault code to the outside through a 422 bus.

Compared with the prior art, the invention has the beneficial effects that: the overcurrent and overvoltage protection function of the output voltage of the product is realized, BIT detection is carried out on the output voltage, the reliability of the product is improved, the fault occurrence rate of the product is reduced, and the output voltage is effectively detected.

In addition to the technical problems addressed by the present invention, the technical features constituting the technical solutions, and the advantageous effects brought by the technical features of the technical solutions described above, other technical problems solved by the present invention, other technical features included in the technical solutions, and advantageous effects brought by the technical features will be described in further detail with reference to the accompanying drawings.

Drawings

Fig. 1 is a schematic circuit diagram according to an embodiment of the invention.

Detailed Description

The present invention will be described in further detail below with reference to specific embodiments and drawings. Here, the description of the embodiments is provided to help understanding of the present invention, but the present invention is not limited thereto. In addition, the technical features involved in the embodiments of the present invention described below may be combined with each other as long as they do not conflict with each other.

Referring to fig. 1, an output circuit structure with overcurrent and overvoltage protection and self-test functions is shown.

The method mainly comprises the following steps:

1. the over-current and over-voltage protection module (XC 7388BAC chip is adopted in the embodiment). The leading-out terminals IN (leading-out

terminal numbers

10, 11, 12, 13 and 14) of the U1 chip are power input ports, are connected with an input voltage VCC and are grounded through the ceramic capacitor C1. And the leading-out terminal EN (leading-out terminal number 9) of the U1 chip is an enabling control pin and is connected with an input voltage VCC. The leading-out terminal OVP (leading-out terminal number 8) of the U1 chip is used for setting a pin for inputting an overvoltage protection point, is connected into the divider resistors R1 and R2 to play a role of input terminal overvoltage protection, and is grounded through the ceramic capacitor C2. The leading-out terminal SS (leading-out terminal number 7) of the U1 chip is grounded through the ceramic capacitor C3 and is used for adjusting the soft start time. The terminals OUT (

terminal numbers

1, 2, 16, 17 and 18) of the U1 chip are power output terminals and are grounded through the ceramic capacitor C6 and the transient suppression diode. The leading-out terminal VCP (leading-out terminal number 3) of the U1 chip is an output clamping voltage setting pin, is connected to the voltage dividing resistors R4 and R5, and is grounded through the ceramic capacitor C5. The lead-out terminal ILMT (lead-out terminal number 6) of the U1 chip is a current-limiting point setting pin, is grounded through the current-limiting resistor R3, and is grounded through the ceramic capacitor C4. The terminals GND (terminals No. 4, 5, 19) of the U1 chip are grounded. The transient suppression diode D1 is connected between the output end and the input end of the U1 chip and the U1 chip in parallel.

2. The control module is connected with the output end of the over-current and over-voltage protection module through an S end of the P-channel MOS field effect transistor Qa1, the resistor R7 is connected between an S end and a G end of the P-channel MOS field effect transistor Qa1 in series, the G end of the P-channel MOS field effect transistor Qa1 and the No. 4 pin of the optical coupler U2 are connected in series, the resistor R9 is connected with the No. 3 pin of the optical coupler U2 in ground, the No. 1 pin of the optical coupler U2 is connected with +3.3VD, the leakage current absorption resistor RC1 is connected between the No. 1 pin of the optical coupler U2 and the No. 2 pin of the optical coupler U2 and the resistor Rd1 is connected between the No. 2 pin of the optical coupler U2 and the processor module in.

3. The monitoring module is characterized in that the resistor R6 is connected in series between the G end of the N-channel MOS field effect transistor Qa2 and the D end of the P-channel MOS field effect transistor Qa1, the resistor R8 is connected in series between the G end of the N-channel MOS field effect transistor Qa2 and the ground, the zener diode D3 is connected in parallel at the resistor R8, the S end of the N-channel MOS field effect transistor Qa2 is grounded, and the D end of the N-channel MOS field effect transistor Qa2 is connected with the processor module.

4. The output module is connected with the G end of the P-channel MOS field effect transistor Qa1 of the control module through the positive end of the anti-reverse diode Dt1, and the negative end of the output module outputs the output signal to the outside.

5. The processor module (in this embodiment, a C8051F021 single chip microcomputer is used). The processor controls the optocoupler U2 to work by outputting a ground signal, receives a monitoring signal (ground signal) of the N-channel MOS field effect transistor Qa2, and logically judges whether the external output voltage is normal. And outputs a fault code to the outside through the 422 bus.

The invention has the multifunctional characteristics of overcurrent and overvoltage protection function, BIT monitoring function, fault code output function and the like.

The foregoing merely represents embodiments of the present invention, which are described in some detail and detail, and therefore should not be construed as limiting the scope of the invention. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the inventive concept, which falls within the scope of the present invention. Therefore, the protection scope of the present patent shall be subject to the appended claims.

Claims

1. The utility model provides an output circuit structure with overcurrent and overvoltage protection and self-checking function which characterized in that contains, overcurrent and overvoltage protection module, control module, monitoring module, output module and processor module, overcurrent and overvoltage protection module is used for carrying out the excessive pressure and overcurrent protection to input and output voltage and right control module output voltage, control module is used for the basis processor module output control signal control the voltage output of overcurrent and overvoltage protection module output, monitoring module is used for with control module output voltage exports after handling for processor module carries out BIT and detects, output module is used for with control module's output voltage exports after preventing reverse diode protection.

2. The output circuit structure with the functions of overcurrent and overvoltage protection and self-test as claimed in claim 1, wherein the processor module is configured to output a control signal to the control module, collect a BIT detection signal of the monitoring module, and output a fault code to the outside via a 422 bus.