CMOS Schmitt trigger circuit and associated methods
US9467125B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 17, 2014 |
| Grant date | Oct 11, 2016 |
| Priority date | — |
| Expiry date | Feb 11, 2035 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03K3/3565
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
The Schmitt trigger circuit includes a signal input, a first inverter coupled to the signal input and configured to operate at a first voltage, and a second inverter coupled downstream of the first inverter and configured to operate at a second voltage lower than the first voltage. A protection device is coupled between the first inverter and the second inverter, and configured to limit a voltage input to the second inverter at the second voltage. A feedback circuit is coupled downstream of the protection device between the first inverter and the second inverter and configured to introduce hysteresis. An output circuit is coupled to the second inverter and configured to provide an output signal at the second voltage. The approach provides an architecture for 3.3V receivers designed by using 1.8V devices, without active power consumption from the I/O PAD during transition, and/or that supports CMOS standard levels for 1.8V and 3.3V receivers.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.