The analog multiplexer is used to simplify our measurement,because wihout the multiplexer it would be very time consuming when we would have to manually switch between the sensor structures. The multiplexer we used is an ADGt32 developed by Analog Devices, which can switch between 32 channels. The circuit itself is reduced to a minimum. It contains 32 double pins to connect the structures with the circuit, 8 pins for controll wires and one led to notify that it is connected to a voltage source.

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The circuit to measure temperature is a simple measurement bridge containing a PT1000. The potentiometer mounted is used to adjust reference temperature. Furthermore the circuit contains an amplifier which amplifies the low voltage increase so that temperature can be measured in desired resolution. The circuit contains two supply pins and one pin for analog output.

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