Patent ID: 8748947

Claim:
An apparatus, comprising: an array of sensors, a plurality of sensors in the array having outputs directly connected to a common amplifier node, and each sensor in the plurality including: a chemically-sensitive field effect transistor (chemFET) having a first conduction terminal, a second conduction terminal coupled to a first supply voltage conductor, and a sensor surface; a first transistor having a first conduction terminal coupled to the first conduction terminal of the chemFET, a second conduction terminal coupled to a second supply voltage conductor, and a gate coupled to a bias voltage conductor; and a second transistor having a gate coupled to a corresponding select voltage conductor, a first conduction terminal directly coupled to the first conduction terminal of the chemFET, a second conduction terminal directly coupled to the common amplifier node; an common amplifier having an input connected to the common amplifier node, and an output coupled to an output conductor; and a reset circuit coupled to the common amplifier node.