Subthreshold sense circuit for clamping an injected current
US5202590A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 6, 1991 |
| Grant date | Apr 13, 1993 |
| Priority date | — |
| Expiry date | Nov 6, 2011 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03K5/086
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
A subthreshold sense circuit for clamping an injected current at the input pins of an integrated circuit device before the injected current causes the voltage at the input pins to exceed the supply voltage by more than a diode's ON voltage. The subthreshold sense circuit is driven to operate in the linear region of the FETs. The subthreshold sense circuit of the present invention comprises level shifters, a subthreshold current source, a reference voltage generator, a subthreshold comparator, and a clamping circuit. The subthreshold current source generates a reference drain current to drive the sense circuit of the present invention in the linear region. A level shifter is connected to an input pin to shift the voltage level of the input pin by a subthreshold voltage level. The reference voltage generator provides a reference voltage to be compared with the subthreshold-shifted input voltage. The subthreshold comparator compares the subthreshold-shifted input voltage with the reference voltage level such that when the subthreshold-shifted input voltage from the input pin exceeds the reference voltage level, the subthreshold comparator will turn on. The clamping circuit is activate…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.