Filter circuit and optical disk device including the same
US8350619B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Dec 28, 2011 |
| Grant date | Jan 8, 2013 |
| Priority date | — |
| Expiry date | Dec 28, 2031 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03F2200/91
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A current-mode filter includes a first, a second, and a third transistor having the same channel polarity. The drain of the first transistor is connected to the source of the second transistor functioning as a gate grounded circuit. The drain of the second transistor is connected to the gates of the first and third transistors. A first and a second capacitive element are connected to the gate and drain of the first transistor. The current source supplies a bias current to each of the first and second transistors. The drain of the first transistor is used as an input terminal. An output signal is extracted from a drain current of the third transistor. Therefore, only one transconductance adjustment circuit is enough.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.