Dynamic transducer biasing signal amplifying circuitry
US4050086A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | May 6, 1976 |
| Grant date | Sep 20, 1977 |
| Priority date | — |
| Expiry date | May 6, 1996 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03F3/45991
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
The ideal response expected of an electromagnetic transducer, particularly of the Magneto-Resistive (M-R) type, obtains with signal translating circuitry for amplifying the varying signal produced and for dynamically biasing the transducer for maintaining the transducing operation in the linear portions of the characteristics of both the transducer and the amplifying circuitry. An M-R transducer is connected to the input circuit of alternating signal differential amplifying circuitry for delivering the desired signal at output terminals. The offset voltage across the transducer is compensated by differentially biasing input transistors of the amplifying circuitry. Biasing direct current through and/or voltage across the M-R transducer is controlled by a circuit connected to the output terminal and responsive to the signal thereat for developing a slowly inversely varying unidirectional voltage, preferably within a low pass filter interposed in the control circuit for stability. A current handling device, conveniently a transistor having the control voltage applied to a base electrode, is connected in series with the transducer for dynamically adjusting the unidirectional biasing cu…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.