University of Technical Education Ho Chi Minh City ELECTRONIC CONTROL UNIT (COMPUTER) Le Thanh Phuc Faculty of Automotive Engineering Email: thanhphucckd@gmail.com Introduction A computer is an electronic device that stores and processes data It is also capable of controlling other devices Introduction The computer contains a crystal oscillator or clock circuit that delivers a constant time pulse Signal Conditioning and Conversion Some input sensors produce a very lowvoltage signal of less than volt This signal also has an extremely lowcurrent flow Therefore, this type of signal must be amplified, or increased, before it is sent to the microprocessor Signal Conditioning and Conversion Signal Conditioning and Conversion The digital computer cannot accept analog signals from the sensors and requires an input interface to convert the analog signal to digital The analog to digital (A/D) converter continually scans the analog input signals at regular intervals For example, if the A/D converter scans the TPS signal and finds the signal at volts, the A/D converter assigns a numeric value to this specific voltage Then the A/D converter changes this numeric value to a binary code Signal Conditioning and Conversion Microprocessor The microprocessor (μP) is the brain of the computer The μP brings information into and out of the computer’s memory The registers used include the accumulator, the data counter, the program counter, and the instruction register The control unit implements the instructions located in the instruction register The arithmetic logic unit (ALU) performs the arithmetic and logic functions Microprocessor