High/low voltage tolerant interface circuit and crystal oscillator circuit
US7564317B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jul 6, 2007 |
| Grant date | Jul 21, 2009 |
| Priority date | — |
| Expiry date | Oct 7, 2027 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03B5/36
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
A high/low voltage tolerant interface circuit and a crystal oscillator circuit using the same are provided herein. The interface circuit includes a first transistor, a bulk-voltage generator module and an bias module. The first transistor includes a gate, a first source/drain, a bulk coupled to the first source/drain of the first transistor and a second source/drain coupled to an input node. The bulk-voltage generator module is, used to determine whether a first voltage or a predetermined voltage is being provided to the bulk of the first transistor according to the voltage of the input node. The bias module is coupled to the gate of the first transistor. The bias module is used to provide an bias voltage to the gate of the first transistor and makes the first transistor conduct in order to control the voltage of the second source/drain voltage of the first transistor.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.