JPS6442905A - High frequency gain variable amplifier - Google Patents

High frequency gain variable amplifier

Info

Publication number
JPS6442905A
JPS6442905A JP20017387A JP20017387A JPS6442905A JP S6442905 A JPS6442905 A JP S6442905A JP 20017387 A JP20017387 A JP 20017387A JP 20017387 A JP20017387 A JP 20017387A JP S6442905 A JPS6442905 A JP S6442905A
Authority
JP
Japan
Prior art keywords
gain
high frequency
circuit
amplifier
potential
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
JP20017387A
Other languages
Japanese (ja)
Inventor
Yukio Kabetani
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
NEC Corp
Original Assignee
NEC Corp
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by NEC Corp filed Critical NEC Corp
Priority to JP20017387A priority Critical patent/JPS6442905A/en
Publication of JPS6442905A publication Critical patent/JPS6442905A/en
Pending legal-status Critical Current

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  • Amplifiers (AREA)

Abstract

PURPOSE:To decrease the deterioration in the gain attenuation at a high frequency by providing a differential transistor(TR) amplifier circuit, a control circuit varying the gain of the said amplifier circuit and a passive element circuit with a high frequency low impedance connected to one of output terminals of the differential TR amplifier circuit. CONSTITUTION:An input signal is supplied from an input terminal 8, amplified by a common emitter TR 1 and a common base TR 2 and the result is outputted to an output terminal 9. In this case, the gain control terminal 10 is set to a potential where the base potential oaf the TR 2 is higher than the base potential of the TR 3 to turn off the TR 3 completely thereby maximizing the gain of the amplifier. Then the potential of the gain control terminal 10 is lowered to turn off the TR 2 completely thereby minimizing the gain of the amplifier. The collector of the TR 3 in the amplifier circuit has a low impedance at a high frequency due to the series resonance of the passive component circuit 5 comprising the series resonance circuit. Thus, the deterioration in the gain attenuation at a high frequency is reduced.
JP20017387A 1987-08-10 1987-08-10 High frequency gain variable amplifier Pending JPS6442905A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP20017387A JPS6442905A (en) 1987-08-10 1987-08-10 High frequency gain variable amplifier

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP20017387A JPS6442905A (en) 1987-08-10 1987-08-10 High frequency gain variable amplifier

Publications (1)

Publication Number Publication Date
JPS6442905A true JPS6442905A (en) 1989-02-15

Family

ID=16420007

Family Applications (1)

Application Number Title Priority Date Filing Date
JP20017387A Pending JPS6442905A (en) 1987-08-10 1987-08-10 High frequency gain variable amplifier

Country Status (1)

Country Link
JP (1) JPS6442905A (en)

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