| With the fast development of science and technology and the demand for testing techniques, multimeter with advanced functions plays more and more important role in nation product and defense construction. Our project is to design the handheld multimeter that is with five and a half electric parameter sensitive, and it can measure temperature and altitude. The designed multimeter has a variety of transmission and control interface, and it also can be synchronized by IEEE1588. At present, maintenance engineer go to fix the radar or communication base station often carry different kinds of instruments. So, it is very significance to research handheld multi-function test meter.Our topic complete the scheme selection, hardware design, as well as bottom-driven program, operating system transplant.The specific contents are as follows:1ã€Design of the electric quantity circuit:as the major function of the multimeter,this design is based on efficient,integrated,precision.So,we take multimeter ASIC chips ES51966to achieve our purpose.The internal of ES51966are made of the switch, attenuation network and ADC.So,it saved much space for the circuit board.2ã€Design of the non-electric quantity:design the temperature test circuit,the humidity test circuit,the altitude test circuit,the gradient circuit.And all of the above chips are integrate chip and digital communication.3ã€Design of the PCB board:This topic use the MENTOR Graphics to finsh the PCB board.,and according to the anti-jamming features such as reasonable wiring layout. Eventually make the board size as177mm*111mm.4ã€Program of the bottom driven:we first studied the protocol and deal of each sensor. Then, according to the application sheet, the bottom driver was programmed.After design of the handheld multimeter, we debugged the circuit and test the whole instrument.Electric quantity test reach the standard. |
