Analog-proportional temperature controlle

The performance of the single-ended analog proportional temperature controller in the tracking mode is shown in Fig. 6.4. The measurement was done at room temperature, and the control voltage of microhotplate 1 was increased in steps of 100 mV. For example, a control voltage of 1.60 V produced a microhotplate temperature of approximately 355 °C. Microhotplate 2 was kept at a constant temperature of 200 °C and microhotplate 3 was kept at 350 °C. 

Fig. 6.5. Performance of the single-ended analog proportional temperature controller in the stabilization mode...

The voltage drop across the platinum temperature sensor is small since the platinum resistor has a nominal resistance of only 75 Q. The fully-differential LNA amplifies the minute voltage drop in order to provide an useful feedback signal to the differential-analog proportional controller. A simplified schematic of the fully-differential low-noise amplifier is shown in Fig. 5.18. 

The singled-ended analog architecture comprises a temperature sensor on the bulk chip, three single-ended analog proportional microhotplate temperature controllers... 

Temperature control of the reactor is achieved by varying the analog signal to the valve controlling the cooling water flow. A simple proportional integral controller was used in the experimental model determination. 

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