Amplifiers – With semiconductor amplifying device – Including differential amplifier
Patent
1996-10-29
1998-12-08
Mullins, James B.
Amplifiers
With semiconductor amplifying device
Including differential amplifier
330303, 330305, 330306, 327553, 327558, H03F 345
Patent
active
058476059
ABSTRACT:
A filter circuit comprises three stages 260, 270, 280, each having a differential input and a differential output. The output of stage 260 serves as the input of stage 270 and the output of stage 270 serves as the input of stage 280 respectively. Stage 260 comprises two transistor pairs 201, 202 and 203, 204. An input signal is applied to the base electrodes of transistors 201, 204 which causes a current change in their opposite transistor 202, 203. Transistors 202, 203 have their respective base and collector electrodes connected together. The collector electrodes of transistors 202, 203 constitute the output of stage 260. Stages 270 and 280 have essentially the same structure as stage 260. The arrangement offers high frequency capabilities from a low supply voltage. In another embodiment, a cut-off frequency is varied under control of controllable current sources.
REFERENCES:
patent: 4514704 (1985-04-01), Curtis
patent: 4914401 (1990-04-01), Mader
patent: 5489878 (1996-02-01), Gilbert
Beatson Trevor P
Mihailovits Nicholas
Mullins James B.
Plessey Semiconductors Limited
LandOfFree
Folded active filter does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Folded active filter, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Folded active filter will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-181933