TW200743300A - Variable gain amplifier with gain adjusting circuit - Google Patents

Variable gain amplifier with gain adjusting circuit

Info

Publication number
TW200743300A
TW200743300A TW095149586A TW95149586A TW200743300A TW 200743300 A TW200743300 A TW 200743300A TW 095149586 A TW095149586 A TW 095149586A TW 95149586 A TW95149586 A TW 95149586A TW 200743300 A TW200743300 A TW 200743300A
Authority
TW
Taiwan
Prior art keywords
exponential
circuit
controlling signal
linear
signal
Prior art date
Application number
TW095149586A
Other languages
Chinese (zh)
Other versions
TWI328343B (en
Inventor
Wen-Chang Lee
Ying-Che Tseng
Original Assignee
Via Tech Inc
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 Via Tech Inc filed Critical Via Tech Inc
Publication of TW200743300A publication Critical patent/TW200743300A/en
Application granted granted Critical
Publication of TWI328343B publication Critical patent/TWI328343B/en

Links

Landscapes

  • Amplifiers (AREA)
  • Control Of Amplification And Gain Control (AREA)

Abstract

A variable gain amplifier is disclosed, wherein the variable gain amplifier includes a gain adjusting circuit and an amplifying circuit. The gain adjusting circuit includes a linear exponential transforming circuit, a voltage buffer circuit and a power transforming circuit. The linear exponential transforming circuit receives a linear controlling signal and transforms the linear controlling signal to output an exponential controlling signal. The voltage buffer circuit is electrically connected with the linear exponential transforming circuit to receive the exponential controlling signal and generates a voltage controlling signal and a feedback signal according to the exponential controlling signal and a bias current. The voltage controlling signal controls the amplifying circuit. The power transforming circuit is electrically connected with the linear exponential transforming circuit and the voltage buffer circuit to receive the exponential controlling signal and the feedback signal and take the two times of square root of product of the exponential controlling signal and the feedback signal and then plus the bias current to output a power signal to the linear exponential transforming circuit.
TW95149586A 2006-05-11 2006-12-28 Variable gain amplifier with gain adjusting circuit TWI328343B (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US79932406P 2006-05-11 2006-05-11

Publications (2)

Publication Number Publication Date
TW200743300A true TW200743300A (en) 2007-11-16
TWI328343B TWI328343B (en) 2010-08-01

Family

ID=38697682

Family Applications (1)

Application Number Title Priority Date Filing Date
TW95149586A TWI328343B (en) 2006-05-11 2006-12-28 Variable gain amplifier with gain adjusting circuit

Country Status (2)

Country Link
CN (1) CN100578926C (en)
TW (1) TWI328343B (en)

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP6085910B2 (en) 2012-06-29 2017-03-01 オムロン株式会社 Photoelectric sensor and method for controlling amplification of received light amount in photoelectric sensor
CN105720938B (en) * 2016-01-22 2018-01-05 西安电子科技大学 A kind of linear ultra wide band variable gain amplifiers of dB
CN109150112A (en) * 2018-08-01 2019-01-04 电子科技大学 Ultra wide band variable gain mixer

Also Published As

Publication number Publication date
CN100578926C (en) 2010-01-06
TWI328343B (en) 2010-08-01
CN101009479A (en) 2007-08-01

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