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