The ICL7136 is the IC of the CMOS that the function to measure the voltage of the input correctly, the function to control the LCD(Liquid Crystal Display) and so on are housed in 1 chip. It is possible to measure the voltage to Â±200 mV or Â±2 V. The ICL7136 is the type which uses the LCD as the display. There is the ICL7137 in the type which uses the LED for the display. The control signal of the LCD is the square wave of the frequency is about 60 Hz(48KHz/800) and the voltage is 5.5Vp-p.
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