Analyze the working principle of car ECU and the evolution of architecture

Lead: Zhu Yulong wrote in the article that historically, the ECU architecture of the security system is from 3MCU=”2MCU=”1 multi-core MCU+external monitor, dual MCU, or MCU+external ASICMCU architecture. There are two points in the software: First, the main MCU and the monitoring MCU use Hearbeat to monitor the working status of the MCU, and the second is to use Data Mirroring to monitor the operation status.

ECU (electronic control unit) is an electronic control unit, which refers to all electronic control systems on a car. It consists of three parts: input circuit, microcomputer and output circuit. With the increasing automation of automotive electronics, more and more ECUs have appeared in auto parts, and the complexity between lines has increased dramatically.

The ECU has an input processing circuit, a microprocessor, an output processing circuit, a system communication circuit, and a power supply circuit, and its structure is as follows:

Working principle: The input circuit accepts the signals input by the sensor and other devices, filters and amplifies the signal, and then converts it into a certain volt input level; the signal sent from the sensor to the ECU input circuit has both analog and digital signals, input The analog/digital converter in the circuit can convert the analog signal into a digital signal and then transmit it to the microcomputer; the microcomputer processes the above preprocessed signal and sends the processed data to the output circuit; the output circuit converts the digital information The power is amplified, and some are restored to analog signals, which drive the controlled servo components to operate.

According to "Delphi Secured Microcontroller Architecture", it describes the architecture of Delphi's dual-core MCU + external monitor. As shown below:

Historically, the ECU architecture of the security system is from 3MCU=”2MCU=”1 multicore MCU+external monitor.

The architecture of the dual MCU, or MCU+ external ASICMCU, is as follows:

1) The main MCU and the monitoring MCU both read the corresponding sensor signals

2) Monitoring MCU can control the transaxle

3) Both the main MCU and the monitoring MCU have separate Hardware watchdog