JPS644108A - Gain variable type amplifier circuit - Google Patents

Gain variable type amplifier circuit

Info

Publication number
JPS644108A
JPS644108A JP15756387A JP15756387A JPS644108A JP S644108 A JPS644108 A JP S644108A JP 15756387 A JP15756387 A JP 15756387A JP 15756387 A JP15756387 A JP 15756387A JP S644108 A JPS644108 A JP S644108A
Authority
JP
Japan
Prior art keywords
trs
gain variable
amplifier circuit
variable type
type amplifier
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.)
Granted
Application number
JP15756387A
Other languages
Japanese (ja)
Other versions
JPH0630424B2 (en
Inventor
Toshiyuki Okamura
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 JP15756387A priority Critical patent/JPH0630424B2/en
Publication of JPS644108A publication Critical patent/JPS644108A/en
Publication of JPH0630424B2 publication Critical patent/JPH0630424B2/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Landscapes

  • Control Of Amplification And Gain Control (AREA)

Abstract

PURPOSE:To make the gain variable by connecting transistor(TRs) to a load of a TR for differential amplification in cascade respectively and connecting bases in common so as to make the output center voltage constant. CONSTITUTION:TRs Q1, Q2, Q7, Q12 are connected in cascade with TRs Q4, and Q3, Q5 and Q6, Q7 and Q8, and Q11 and Q10 respectively. Then in changing the potential difference of control voltages V2, V3 at control terminals 3, 4 to change the gain, the collector-base voltage of the TRs Q3-Q8, Q10, Q11 is made constant thereby avoiding the effect of the Early effect (a phenomenon that IC is not saturated but increased slightly when VC reaches a prescribed value in the VC-IC characteristic). Then the production of a difference in the collector current of sets of TRs Q3, Q7, Q4, Q8, Q5, Q10, Q6, Q11 is prevented.
JP15756387A 1987-06-26 1987-06-26 Variable gain type amplifier circuit Expired - Lifetime JPH0630424B2 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP15756387A JPH0630424B2 (en) 1987-06-26 1987-06-26 Variable gain type amplifier circuit

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP15756387A JPH0630424B2 (en) 1987-06-26 1987-06-26 Variable gain type amplifier circuit

Publications (2)

Publication Number Publication Date
JPS644108A true JPS644108A (en) 1989-01-09
JPH0630424B2 JPH0630424B2 (en) 1994-04-20

Family

ID=15652415

Family Applications (1)

Application Number Title Priority Date Filing Date
JP15756387A Expired - Lifetime JPH0630424B2 (en) 1987-06-26 1987-06-26 Variable gain type amplifier circuit

Country Status (1)

Country Link
JP (1) JPH0630424B2 (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH01288101A (en) * 1988-05-16 1989-11-20 Iwatsu Electric Co Ltd Gain switching circuit
US6177839B1 (en) * 1998-02-20 2001-01-23 Nec Corporation Variable gain amplifier circuit

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH01288101A (en) * 1988-05-16 1989-11-20 Iwatsu Electric Co Ltd Gain switching circuit
US6177839B1 (en) * 1998-02-20 2001-01-23 Nec Corporation Variable gain amplifier circuit

Also Published As

Publication number Publication date
JPH0630424B2 (en) 1994-04-20

Similar Documents

Publication Publication Date Title
GB1479008A (en) Amplifier circuit
GB1413217A (en) Circuit for shifting the dc level of a signal
JPS5591219A (en) Amplifier
JPS54147761A (en) Gain control unit
JPS644108A (en) Gain variable type amplifier circuit
JPS5750139A (en) Hysteresis circuit
ES8200801A1 (en) Variable-gain differential amplifier
JPS57166670A (en) Division circuit
JPS6450604A (en) High gain amplifier using two current mirrors
JPS5648716A (en) Offset voltage compensating circuit
JPS56153816A (en) Signal processing circuit
JPS5750115A (en) Gain control circuit
JPS56161707A (en) Signal processing circuit
JPS6477208A (en) Differential amplifying circuit
JPS5728407A (en) Amplifying circuit
JPS57196609A (en) Gain adjusting circuit
JPS55166342A (en) Minute potential difference comparing circuit
JPS5564420A (en) Variable impedance circuit
JPS55115708A (en) Push pull amplifier
JPS59131210A (en) Gain controlling amplifier
JPS57103434A (en) Frequency dividing circuit
JPS55133115A (en) Variable gain amplifying circuit
JPS55127725A (en) Voltage comparator
JPS57181215A (en) Variable gain circuit
JPS5783913A (en) Current amplifying circuit