Amplifier with folded super-followers
US6356152B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Jul 16, 2000 |
| Grant date | Mar 12, 2002 |
| Priority date | — |
| Expiry date | Jul 16, 2020 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03F2203/45702
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
Fixed gain amplifiers have particular use in the read channel of hard disk drives. A CMOS fixed gain amplifier 18c having a constant gain over the large dynamic range of hard disk drive applications is provided by incorporating super follower transistors M3 and M4 into the input stage of the fixed gain amplifier. The super follower transistors are folded into the output stage of the amplifier. The differential current through the degeneration resistor RE1 travels through the super follower transistors M3 and M4 and into the current mirrors I5 and I6. Thus the ac differential current goes directly to the cascoded stage, into the load resistors RL1 and RL2, and to the output load.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.