Regenerative circuits for rapid biosensing

Integrated DNA-sensor arrays check for probe-target hybridization by detailed analysis of the sensed capacitance changes, normally off-chip and with attendant area and power costs. However, portable medical applications often require only a quick 1-b answer: the detection of a reaction event. We reduce the overhead for this task manifold with simple regenerative analog and mixed-signal circuits, including a 9-b low-power rail-to-rail comparator and a winner-take-all (WTA) circuit. Simulation of a design targeted for implementation in a 0.35μm CMOS process is presented.