Frequency adjustable, zero temperature coefficient referencing ring oscillator circuit
US5661428A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 15, 1996 |
| Grant date | Aug 26, 1997 |
| Priority date | — |
| Expiry date | Apr 15, 2016 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG05F3/242
- WIPO fieldControl
- WIPO sectorInstruments
Abstract
A frequency adjustable, zero temperature coefficient referencing ring oscillator circuit includes a plurality of inverter stages each having a switching circuit that produces the oscillating output signal for the ring oscillator circuit and a control circuit that controls the switching circuit to establish the frequency of the output signal, the control circuit including field-effect transistors which are operated as output resistance controllable devices and which have their operating points, and thus their output resistances, established by a reference voltage that is produced by a precision reference voltage generating circuit so that the operating frequency of the ring oscillator circuit can be set by adjusting the value of the reference signals produced by the precision reference signal generating circuit and is maintained at the setpoint value because the precision reference voltage generating circuit operates independently of variations in temperature and/or the power supply voltage. The ring oscillator circuit is fabricated as an integrated circuit device and the operating frequency of the integrated circuit ring oscillator circuit can be adjusted after fabrication and pass…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.