Capacitive charge pump

Abstract

One or more charge pumps may be used to amplify the output voltage from a chemically-sensitive pixel that comprises one or more transistors. A charge pump may include a number of track stage switches, a number of boost phase switches and a number of capacitors. The capacitors are in parallel during the track phase and in series during the boost phase, and the total capacitance is divided during the boost phase while the total charge remains fixed. Consequently, the output voltage is pushed up.

What is claimed is: 
     
         1 . A circuit, comprising:
 an input line coupled to a chemically-sensitive pixel array;   a first charge pump; and   an output line, wherein the chemically-sensitive pixel array comprises a plurality of chemically-sensitive pixels, each pixel comprising a chemically-sensitive transistor.