Technologies Available for License

2013-010: Method and Apparatus for Discriminating Small Signals

Invention: 2013-010

Patent Status: U.S. Patent Number 9,225,325 was issued on December 29, 2015

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Summary

Real-world signals that we would like to detect are usually analog in nature. A sensor detects the signal and, in this case, converts it to an electrical charge which is then amplified to a convenient level by a charge amplifier. The amplified charge is filtered, resulting in a pulse which is compared to a threshold in a discriminator. If the pulse amplitude exceeds the predetermined threshold, generally set to be just above the expected noise level, it proceeds to be processed and converted to digital form. If its amplitude does not exceed the threshold, the pulse is ignored and no more power is consumed by the system to process it. Unfortunately, hysteresis in the comparator circuit can result in pulses that exceed the noise limit being ignored. The inventive analog circuit maintains hysteresis in the comparator circuit to allow the circuit to operate at high speeds, but also allows true pulses to be detected even if their amplitudes fall below the hysteresis threshold.

Description

A comparator circuit is disclosed. The comparator circuit includes a differential input circuit, an output circuit, a positive feedback circuit operably coupled between the differential input circuit and the output circuit, and a hysteresis control circuit operably coupled with the positive feedback circuit. The hysteresis control circuit includes a switching device and a transistor. The comparator circuit provides sub-hysteresis discrimination and high speed discrimination.

Journal Publication & Intellectual Property

• VMM1 - An ASIC for Micropattern Detectors (.pdf)
• US 9,225,325 B2 (.pdf)