Nonvolatile nonlinear programmable electronic potentiometer
US5084667A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 22, 1989 |
| Grant date | Jan 28, 1992 |
| Priority date | — |
| Expiry date | Dec 22, 2009 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG05B2219/23041
- WIPO fieldControl
- WIPO sectorInstruments
Abstract
A variable impedance circuit for use in an external circuit is disclosed. The impedance value is selected by an external circuit. The variable impedance is generated between two terminals which are accessible for connection to external circuitry. The impedance provided between these terminals is determined by a control circuit responsive to electrical signals coupled to the control circuit. An internal register in the control circuit stores a value which specifies the impedance between the two terminals. The stored value is copied into a programmable nonvolatile read-only memory in response to a first predetermined electrical signal. Similarly, the value stored in the read-only memory is selectively copied into the internal control circuit register in response to a second predetermined electrical signal. A number of embodiments of variable impedance elements are disclosed which minimize the number of separate resistors required to achieve the equivalent resolution achievable using a series arrangement of resistors.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.