28V or open-circuit discrete magnitude output circuit

Abstract

The invention provides a 28V or open-circuit discrete magnitude output circuit which comprises an FPGA, a bus driver, an inverter, a Darlington tube, a pull-up resistor R1, a power distribution point and an NMOS tube, and the discrete magnitude output circuit is used for outputting open circuit to a controlled product before the FPGA is powered on and logic operation loading is completed, or outputting 28V to the controlled product after the FPGA is powered off abnormally. According to the 28V or open-circuit discrete magnitude output circuit designed by the invention, an initial state is output to a controlled product before the product is powered on and subjected to arithmetic logic loading until the logic does not run; and when the product is powered off or other abnormal conditions occur, the safety state is output to the controlled product, so that the adaptability is improved, and the safety and reliability of the airborne electromechanical system are enhanced.

Description

technical field [0001] The invention belongs to the field of airborne computers and relates to circuit design technology, specifically a 28V or open-circuit discrete output circuit, which is suitable for the initial state and safe state of products required by airborne electromechanical systems (airborne finished remote interface unit products) Inconsistent discrete output states. Background technique [0002] Airborne electromechanical systems often involve the control of various valves and pumps such as solenoid valves and combined valves, and the control of the connection, disconnection, and action of valves / pumps. Usually, airborne finished remote interface unit products (hereinafter referred to as products) are used. ) Output 28V or output open circuit control. [0003] At present, in the product-to-valve / pump control, the output state of the product is consistent in both the initial state and the safe state, that is, the initial state and the safe state of the product...

AI Technical Summary

Problems solved by technology

The above control method has the following problems: If the initial state and safe state of the product are both designed to be open, the system security cannot be guaranteed; if the initial state and safe state of the product are both designed to be 28V, there will be short The output is 28V, which causes the valve / pump to open and close for a short time. On the one hand, it affects the life of the valve / pump. On the other hand, there is oil leakage in the system, especially the fuel system, which seriously affects the safety of the airborne electromechanical system.

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