JPS54120561A - Automatic gain control amplifier - Google Patents

Automatic gain control amplifier

Info

Publication number
JPS54120561A
JPS54120561A JP2735678A JP2735678A JPS54120561A JP S54120561 A JPS54120561 A JP S54120561A JP 2735678 A JP2735678 A JP 2735678A JP 2735678 A JP2735678 A JP 2735678A JP S54120561 A JPS54120561 A JP S54120561A
Authority
JP
Japan
Prior art keywords
agc
constant value
buffer unit
control current
controller
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
JP2735678A
Other languages
Japanese (ja)
Other versions
JPS6221284B2 (en
Inventor
Susumu Sasaki
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.)
Fujitsu Ltd
Original Assignee
Fujitsu Ltd
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 Fujitsu Ltd filed Critical Fujitsu Ltd
Priority to JP2735678A priority Critical patent/JPS54120561A/en
Publication of JPS54120561A publication Critical patent/JPS54120561A/en
Publication of JPS6221284B2 publication Critical patent/JPS6221284B2/ja
Granted legal-status Critical Current

Links

Classifications

    • HELECTRICITY
    • H03ELECTRONIC CIRCUITRY
    • H03GCONTROL OF AMPLIFICATION
    • H03G3/00Gain control in amplifiers or frequency changers
    • H03G3/20Automatic control
    • H03G3/30Automatic control in amplifiers having semiconductor devices
    • H03G3/3005Automatic control in amplifiers having semiconductor devices in amplifiers suitable for low-frequencies, e.g. audio amplifiers

Landscapes

  • Engineering & Computer Science (AREA)
  • Multimedia (AREA)
  • Control Of Amplification And Gain Control (AREA)

Abstract

PURPOSE:To eliminate probability that unstable operation of oscillation, etc., is caused while having small compressibility, by attaining constant gain amplification with an AGC control current suppressed to a constant value when a detection becomes below an inferior threshold level. CONSTITUTION:Controller 13 is provided between detector 11 detecting an output signal and buffer unit 12 converting this detected output into an adequate current value. The output signal is applied as an AGC control current to respective control amplifiers 2-1 to 2-n by way of detector 11 and buffer unit 12. At this time, controller 13 when the detection 11 output becomes below a fixed value controls buffer unit 12 to suppress the AGC control current to a constant value and, in consequence, the operation gain of the AGC amplifier decreases down to a constant value, so that the unstable-operation state can be avoided. Next, if a signal of more than the constant value arrives in this state, controller 13 detects that the detection 11 output becomes above the constant value and resets the above-mentioned suppression on buffer unit 12. As a result, the AGC control current increases and the AGC amplifier returns the original gain state, thereby starting the AGC operation.
JP2735678A 1978-03-10 1978-03-10 Automatic gain control amplifier Granted JPS54120561A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP2735678A JPS54120561A (en) 1978-03-10 1978-03-10 Automatic gain control amplifier

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP2735678A JPS54120561A (en) 1978-03-10 1978-03-10 Automatic gain control amplifier

Publications (2)

Publication Number Publication Date
JPS54120561A true JPS54120561A (en) 1979-09-19
JPS6221284B2 JPS6221284B2 (en) 1987-05-12

Family

ID=12218752

Family Applications (1)

Application Number Title Priority Date Filing Date
JP2735678A Granted JPS54120561A (en) 1978-03-10 1978-03-10 Automatic gain control amplifier

Country Status (1)

Country Link
JP (1) JPS54120561A (en)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5690011U (en) * 1979-12-14 1981-07-18
JPS5714514U (en) * 1980-06-30 1982-01-25
JPS5934729A (en) * 1982-08-20 1984-02-25 Mitsubishi Electric Corp Power saving type communication equipment

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR100880065B1 (en) * 2001-07-06 2009-01-22 엔엑스피 비 브이 A communication system and arrangements comprising such a communication system

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5690011U (en) * 1979-12-14 1981-07-18
JPS5714514U (en) * 1980-06-30 1982-01-25
JPS5934729A (en) * 1982-08-20 1984-02-25 Mitsubishi Electric Corp Power saving type communication equipment

Also Published As

Publication number Publication date
JPS6221284B2 (en) 1987-05-12

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