ACTIVE CHEMICALLY-SENSITIVE SENSORS WITH IN-SENSOR CURRENT SOURCES

摘要

Methods and apparatus relating to FET arrays for monitoring chemical and/or biological reactions such as nucleic acid sequencing-by-synthesis reactions. Some methods provided herein relate to improving signal (and also signal to noise ratio) from released hydrogen ions during nucleic acid sequencing reactions.

主权项

1. A method of operating an apparatus comprising an array of chemically sensitive sensors comprising chemically-sensitive field effect transistors (chemFETs) and source follower amplifiers arranged in rows and columns, the method comprising:
inducing a flow of current in the chemFETs in the sensors using a transistor coupled to the chemFET and biased in a current limiting mode; amplifying a voltage on a conduction terminal of the chemFET using a source follower amplifier in the row of the sensors to produce a sensor output voltage; and coupling the sensor output voltage to a column bus coupled to a column of sensors in the array.