Voltage-controlled filter circuit, a semiconductor integrated ci

Details Voltage-controlled filter circuit, a semiconductor integrated ci Voltage-controlled filter circuit, a semiconductor integrated ci

1995-04-26

1997-03-25

Callahan, Timothy P.

Miscellaneous active electrical nonlinear devices, circuits, and

Specific identifiable device, circuit, or system

Unwanted signal suppression

327553, 327563, 330252, H03B 100

Patent

active

056148607

ABSTRACT:
A voltage-controlled filter circuit has a cutoff frequency directly proportional to a ratio of two current values. The filter circuit comprises a variable conductance circuit having two bipolar junction input transistors supplied with an input voltage signal at the bases thereof and a first variable current source at each emitter thereof. The collectors supply the bases of a pair of differential transistors. A second variable current supply is coupled to common emitters of the pair of differential transistors. Externally supplied control signals set the two current values of the variable current sources. The filter circuit may be manufactured as a semiconductor integrated circuit device for signal processing for use in processing a recorded signal read from a recording medium. The recorded signal is supplied to a semiconductor integrated circuit for signal processing to remove unwanted signal and noise components. Specific unwanted signal components may be removed and noise components whose frequencies exceed a cutoff frequency of a low-pass filter provided in a semiconductor integrated circuit are removed.

REFERENCES:
patent: 4306198 (1981-12-01), Okada
patent: 4404529 (1983-09-01), Rossum et al.
patent: 4528515 (1985-07-01), Gross
patent: 5182477 (1993-01-01), Yamasaki et al.
patent: 5250917 (1993-10-01), Honda et al.
patent: 5396188 (1995-03-01), Aoki
patent: 5418494 (1995-05-01), Betti et al.
patent: 5463349 (1995-10-01), Petersen et al.
Anarogu IC no Kino Kairo Sekkei Nyumon, CQ Publishing Co., LTD, 2992, "Primer of Designing Functional Circuits for Analog ICs".

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