CC-PAIX01 51405038-275 Operational Amplifier

CC-PAIX01 51405038-275 pin 2 and its pin 3 virtual break, that is to say, CC-PAIX01 51405038-275 pin 2 has no current output, so there is I2 = I1. In other words, we get a constant current output of 0.5mA at C. Since the voltage signal at the ends of the Pt resistance temperature sensor measured by CC-PAIX01 51405038-275 is weak, this voltage must be amplified by an amplifier circuit before A/D conversion.

The input signal of CC-PAIX01 51405038-275 is between 50mV and 70mV, and the voltage range for A/D conversion is 0V to 2.5V. After calculation, the amplifier circuit can meet the requirement of A/D conversion when the amplification is about 35 times. Ordinary operational amplifiers are generally more than hundreds of microvolts of input offset voltage, the temperature coefficient of the offset voltage is more than a few microvolts above zero.

CC-PAIX01 51405038-275 Although the input offset voltage can be zeroed, the drift is difficult to eliminate. The chopper-stabilised zero-type operational amplifier TLC2652 provides an inexpensive solution to the problem of micro-signal amplification. The chopper-stabilised zero operation gives the TLC2652 excellent DC characteristics, with an out-of-phase voltage of 0.5 μV (typical) to 1 μV (maximum); an input out-of-phase drift voltage of 0.003 μV/°C (typical), and a long-term out-of-phase voltage drift of 0.003 μV/month [3][8]. After calculation, the performance parameters of the TLC2652 can meet the requirements of the measurement accuracy of this system, so the op-amp in the amplifier circuit of this system uses the TLC2652.