Combined read and write VCO for DASD PRML channels
US6313962A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 16, 1998 |
| Grant date | Nov 6, 2001 |
| Priority date | — |
| Expiry date | Dec 16, 2018 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03L7/093
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
A combined read and write VCO for data channels is disclosed. The combined read and write VCO for data channels shares a common loop capacitor while providing optimal read and write VCO loop responses, and allows the VCO to relock to the write timebase after a read very quickly while maintaining an accurate timebase. The combined read and write VCO includes an oscillator providing an output signal having a frequency that varies proportionately to an oscillator input signal and an adjustable voltage source, the adjustable voltage source having a first configuration for a write mode and a second configuration for a read mode, and the adjustable voltage source providing the oscillator input signal to the oscillator in response to receiving an input current signal. The adjustable voltage source includes a first and second capacitor coupled in series and a switch coupled across the second capacitor, the switch being open to provide the first configuration and closed to provide the second configuration. The oscillator further includes a transconductance amplifier for receiving the input signal from the adjustable voltage source and converting the input signal to a current signal having a…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.