Method and circuit for auxiliary vehicle-mounted equipment to precisely recognize ACC state

Abstract

The invention relates to a method and circuit for auxiliary vehicle-mounted equipment to precisely recognize ACC state. A voltage regulating property of a voltage-regulator tube and a voltage dividingproperty of a resistor are used, an AD collecting method is adopted to realize the detection of the ACC state, ACC is processed under different state, normal starting and closing of equipment are realized, the circuit is simple, the cost is low, and the precision of the state detection is high; and the deficiency that an ACC threshold value is hard to set due to the fact that external factors exist is overcome, the precision of setting of the ACC threshold value is improved, the controllability is high, the stability is high, and the circuit has universality. According to the method and circuit for the auxiliary vehicle-mounted equipment to precisely recognize the ACC state, serial port communication and SPI communication are adopted to realize data interaction, on-off state of the equipment is controlled in real time and real-time state alarming is carried out, and the stability of a system and intelligence of the equipment are improved; and in the installing process of the equipment, whether the AC state is abnormal or not can be rapidly detected and voice alarm is carried out, meanwhile, the equipment is turned off as usual, the condition that the equipment can be normally turned off under the abnormal state of ACC OFF is ensured, and unnecessary power consumption of a battery on a vehicle is prevented.

Description

technical field [0001] The present invention relates to vehicle-mounted control technology, and more specifically, relates to a method for assisting vehicle-mounted equipment to accurately identify the ACC state, and a circuit for assisting the vehicle-mounted equipment to accurately identify the ACC state. Background technique [0002] With the development of the automobile era, on-board electronic products are used more and more widely in the car, which also makes the electronic wiring on the car more and more complicated. The car body itself is a complex floating ground. If the electronic equipment in the car is not well grounded, or there are problems such as series electricity between devices, there will be a certain amount of voltage between the ACC and the ground when the ACC is OFF on the car. [0003] In the application of vehicle multimedia entertainment system products, the ignition switch ACC on the vehicle is generally used to trigger the startup and shutdown. ...

AI Technical Summary

Problems solved by technology

If there are multiple CPUs that need to detect the ACC state during the operation of the equipment, the impact will be more obvious, and the threshold value of ACC will be more difficult to control

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