Software and hardware techniques for a single-chip fingerprint sensor/identifier

The single-chip fingerprint sensor/identifier is based on a new chip concept in which the fingerprint sensor is stacked above the identification circuit, and the identification circuit features a pixel-parallel structure. To realize the concept and improve the identification accuracy and chip reliability, various software and hardware techniques were devised. The software techniques enhance and identify a sensed fingerprint image on the pixel-parallel identification circuit. The hardware techniques provide the circuit and device that execute the software with a high reliability. Test chip performance indicates that the accuracy, power consumption, and speed of identification are sufficient for practical use. A fingerprint identification system on a chip was constructed using these software and hardware techniques.