Abstract
This design introduces the design and research for 4 3/4 Digit DMM Circuit integrally and systemically. The design uses the special DMM chip MAX134 from MAXIM Company as the central IC, which acts as A/D converter, and matches the Microcomputer MCS8051 from Intel Company. In this design, the whole system instructure is constituted by MAX134 and some peripheral component, then connect with the Microcontroller 8051 to drive the LED figures. The article mainly introduces the performance Characteristic of MAX134, inside structure, digital interface, input and output data, and some main functions. The design of intelligent digital multimeter consists of hardware circuit and software circuit. Hardware circuitelesign includes the choice of Microcontroller, the design of circuit and the choice of outside equipment etc. After the hardware circuit fixed, the main function of the instrument will be realized by the software.
Key words: The digital Multimeter; The Microprocessor.; MAX134; 8051。