Oscillation circuit with temperature-dependent current source
US7548131B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | May 29, 2007 |
| Grant date | Jun 16, 2009 |
| Priority date | — |
| Expiry date | Dec 11, 2027 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03K3/03
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
An output signal ZA of NAND 48a is given to a first input of NAND 48b and is given to a second input of the above NAND 48b, simultaneously through a delay circuit. Furthermore, an output signal ZB of the NAND 48b is given to the first input of NAND 48a and is given to the second input of NAND 48a, simultaneously through a delay circuit. The delay circuit includes a charging and discharging circuit consisting of a NMOS 42 having the conductivity controlled by a voltage VN depending on a temperature signal from a temperature-dependent current source 30 and a capacitor 44, and a NMOS 45 being turned on/off by the voltage of the above capacitor 44. By setting temperature characteristics of the voltage VN and temperature characteristics of the threshold voltage of the NMOS 45 so as to cancel each other, the oscillation frequency variation of the oscillation circuit consisting of astable multi-vibrators can be restrained.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.