Title:
FILTER CIRCUIT
Document Type and Number:
Japanese Patent JP3497022
Kind Code:
B2
Abstract:
PROBLEM TO BE SOLVED: To provide the filter circuit consisting of capacitors and MOS transistors(TRs) and having a Q multiple circuit suitable for MOS circuit integration.
SOLUTION: A voltage is applied to a noninverting input terminal of an operational amplifier 16 from a 1st stage of MOS diodes 8, 7 connecting in series with a constant current source 9 and a voltage is applied to a gate of MOS resistor 15 from a 2nd stage of MOS diodes 11, 12 connected in series with a constant current source 10. The DC operating point is made stable by using the MOS resistance 15. An output of a filter 3 is fed back by a coefficient consisting of a ratio of a capacitance 17 to a capacitance 14 and added to the input 4 to form a Q multiple circuit.
Inventors:
Yuji Yamamoto
Application Number:
JP23979295A
Publication Date:
February 16, 2004
Filing Date:
September 19, 1995
Export Citation:
Assignee:
Seiko Instruments Inc.
International Classes:
H03H11/12; (IPC1-7): H03H11/12
Domestic Patent References:
| JP265309A | ||||
| JP5173859A |
Attorney, Agent or Firm:
Masaaki Sakaue