Analog front-end architecture for capacitive pressure sensor

Abstract

An analog front-end architecture for a capacitive pressure sensor with a low-noise amplifier unit for amplification of sensor signals from the sensor. The amplifier unit includes first and second integrator units for integrating charges injected into input terminals of the amplifier unit and for outputting integrated charges to output terminals of the amplifier unit, a feedback unit, and a startup unit. The feedback unit reinjects integrated charges from the integrator unit into the input terminals of the amplifier unit. The startup unit is switchable between first and second switching states and is configured, in the first switching state, to route the charges injected into the input terminals past the first integrator unit into the second integrator unit and from the second integrator unit into the feedback unit, and, in the second switching state, to route charges injected into the input terminals directly into the first integrator unit.