Low frequency filter in a monolithic integrated circuit
US5168180A · kind A · utility
9Cited by
5References
18Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Apr 20, 1992 |
| Grant date | Dec 1, 1992 |
| Priority date | — |
| Expiry date | Apr 20, 2012 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03H11/126
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
A low-pass filter circuit is disposed on a monolithic integrated circuit. An operational amplifier receives a reference potential and drives three parallel stacked diode paths into a current supply. One of the stacked diode paths conducts the vast majority of the current allowing the transistors of the other two stacked diode paths to operate in a sub-threshold region and represent an extremely high resistance. The high resistances in combination with a low value capacitor realizes a low-pass filter on the monolithic integrated circuit.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.