Integrated signal conditioning for silicon pressure sensors

A silicon-diaphragm pressure sensor containing on-chip circuitry for signal conditioning has been designed for applications in biomedicine. The device requires no off-chip components and only two external leads, making it suitable for use with multisensor catheters having diameters less than 1.5 mm. The output is a temperature-compensated high-frequency FM analog representation of the applied pressure signal. The device exhibits 1-percent resolution and accuracy over the physiological pressure and temperature ranges. Circuit techniques applicable to a variety of active sensors are descried.