Gain control circuit for synchronous waveform sampling
US5297184A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 1, 1993 |
| Grant date | Mar 22, 1994 |
| Priority date | — |
| Expiry date | Feb 1, 2013 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03G3/3036
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
A mixed analog and digital gain control circuit for controlling the amplitude of an analog input signal. The circuit has a variable gain amplifier that receives the signal from a read/write recording head preamplifier. The output of the variable gain amplifier is connected through a multiplexer and equalizer to an analog to digital converter for converting the analog signal to digital sample values at controlled sampling times. A gain control circuit receives the digital values and the output of a pulse detector indicating when a pulse has occurred. A gain error detector within the gain control circuit determines the amount of error in the amplitude of each detected pulse, and this error amount is filtered and sent through a digital to analog converter and then through an exponentiating circuit. The output of the exponentiating circuit is connected to a gain control input of the variable gain amplifier.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.