A MOS switched capacitor ladder filter in SIMOX technology for high temperature applications up to 300 degrees Celsius

This paper describes techniques and methods used to realize a seventh order switched capacitor low pass filter in SIMOX technology. The filter has bessel characteristic and a 3dB-bandwidth of 20Hz at a clock frequency of 100kHz. Special design of transistors and transmission gates results in drastically reduced leakage currents. The power supply voltage is 10V. The temperature range is extended up to 300øC. Experimental results of this filter are presented.