Life Technologies Corporation

Peter M Levine

Mark James Milgrew

Kim L Johnson

Jeremy Christopher Jordan

Todd Rearick

The described embodiments may provide a chemical detection circuit that may comprise a plurality of first output circuits at a first side and a plurality of second output circuits at a second side of the chemical detection circuit. The chemical detection circuit may further comprise a plurality of tiles of pixels each placed between respective pairs of first and second output circuits. Each tile may include four quadrants of pixels. Each quadrant may have columns with designated first columns interleaved with second columns. Each first column may be coupled to a respective first output circuit in first and second quadrants, and to a respective second output circuit in third and fourth quadrants. Each second column may be coupled to a respective second output circuit in first and second quadrants, and to a respective first output circuit in third and fourth quadrants.

Semiconductor-based chemical detection device

Chemical detection device having multiple flow channels

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.

Capacitive charge pump

Array configuration and readout scheme

The described embodiments may provide a chemical detection circuit with an improved signal-to-noise ration. The chemical detection circuit may include a current source, a chemical detection pixel, an amplifier and a capacitor. The chemical detection pixel may comprise a chemical-sensitive transistor that may have a first and second terminals and a row-select switch coupled between the current source and chemically-sensitive transistor. The amplifier may have a first input and a second input, with the first input coupled to an output of the chemically-sensitive transistor via a switch and the second input coupled to an offset voltage line. The capacitor may be coupled between an output of the amplifier and the first input of the amplifier. The capacitor and amplifier may form an integrator and may be shared by a column of chemical detection pixels.

Array column integrator

Methods are described for reading a chemically-sensitive field-effect transistor (chemFET) with an improved signal-to-noise ratio. In one embodiment, a method is described for reading a chemFET having a first terminal and a second terminal, and a floating gate coupled to a passivation layer. The method includes biasing the first terminal of the chemFET to a first bias voltage during a read interval. The second terminal of the chemFET is coupled to a data line during the read interval. A current is induced through the chemFET via the data line. An output signal proportional to an integral of a voltage or current on the data line is generated in response to the induced current through the chemFET during the read interval.

Methods for operating an array column integrator

Circuits are described for reading a chemically-sensitive field-effect transistor (chemFET) with an improved signal-to-noise ratio. In one embodiment, a device is described that includes a chemFET including a first terminal and a second terminal, and a floating gate coupled to a passivation layer. An integrator circuit is coupled to the second source/drain terminal of the chemFET via a data line. The integrator circuit applies a bias voltage to the data line during a read interval, thereby inducing a current through the chemFET based on a threshold voltage of the chemFET. The integrator circuit then generates an output signal proportional to an integral of the induced current through the chemFET during the read interval.

Growing community of inventors

Toronto, Canada

Peter M Levine