The input range is from -0.3V to 11.0V with a 12V supply voltage, output swing ranges from 0.1V to 9.0V, the output offset voltage falls below 50mV and 100mV for the two channels, respectively, input bias current is 30nA to 300nA.
A single chip microprocessor 87C196KC is presented, which can automaticly regulate the output Voltage and frequency of the UPS according to the fluctance of the net voltage and frequency of the generator in order to keep the output voltage stable.
The system can measure and display the output voltage,current and important point temperature values of SMPS,can adjust the output voltage,current,can communicate with PC by RS232 and interface with the other system by RS485. It also can record the failure information of SMPS in the virtual EEPROM using flash memory.
The data transmission mechanism of ISA bus was analyzed and the interface circuit was designed with VHDL,including functions of digital input/output of 16 bits,16 lines analogue input,4 lines D/A output of 16 bits and a 64 bits counter.
In this paper, the principles and applications of AD688 and AD660 are described, and a circuit by using the precision ±10V output of AD688 as the reference source of AD660 and its interface with 8031 microprocessor are introduced.
Based on a brief description of these processors, we have analyzed the timings of multiplexed BCD output and serial output of ICL7135,and proposed two kinds of hardware interfaces and driving software.
The paper puts forward an automatic adjustment method for temperature error based on single chip microprocessor,its basic idea is useing D/A to compose of the feedback compensation loop,and using single chip microprocessor to control the output of D/A to eliminate the zero measuring error which causes by the measuring circuit of electrical bridge and operating point of amplifier varying with temperature,and these make the temperature error to diminish.