JPS61242405A - Variable gain amplifier - Google Patents

Variable gain amplifier

Info

Publication number
JPS61242405A
JPS61242405A JP60083762A JP8376285A JPS61242405A JP S61242405 A JPS61242405 A JP S61242405A JP 60083762 A JP60083762 A JP 60083762A JP 8376285 A JP8376285 A JP 8376285A JP S61242405 A JPS61242405 A JP S61242405A
Authority
JP
Japan
Prior art keywords
resistance
resistances
gain
analog switch
feedback
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
JP60083762A
Other languages
Japanese (ja)
Other versions
JPH0567083B2 (en
Inventor
Koji Oka
浩二 岡
Toshihiko Sakai
堺　俊彦
Shigeto Suzuki
茂人 鈴木
Fumihisa Nakamura
中村　文久
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.)
Panasonic Holdings Corp
Original Assignee
Matsushita Electric Industrial Co 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 Matsushita Electric Industrial Co Ltd filed Critical Matsushita Electric Industrial Co Ltd
Priority to JP60083762A priority Critical patent/JPS61242405A/en
Publication of JPS61242405A publication Critical patent/JPS61242405A/en
Publication of JPH0567083B2 publication Critical patent/JPH0567083B2/ja
Granted legal-status Critical Current

Links

Classifications

    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
    • Y02E60/30—Hydrogen technology
    • Y02E60/50—Fuel cells

Landscapes

  • Control Of Amplification And Gain Control (AREA)

Abstract

PURPOSE:To to reduce the size of a transistor (TR) and to reduce the variance of a process and a gain error due to temperature variation by constituting an inverting amplifier which uses an operational amplifier so that the on resistance of an analog switch which switches an input resistance and feedback resistance is proportional to the resistance value of a changeover resistance. CONSTITUTION:For example, analog switches SW5-SW8 have on resistances Ros1, Ros2, Rof1, and Rof2, which are alpha times (0<alpha<1) as large a changeover resistances, i.e. input resistances Rs1 and Rs2 and feedback resistances Rf1 and Rf2. When the SW5 and SW7 are on, the gain of this inverting amplifier is -(Rf1+Rof1/Rs1+Rof1)=-(Rf1+alphaRf1/Rs1+alphaRs1)=-[Rf1(1+alpha)/Rs1(1 +alpha)]=-R$df1-X/Rs1 and the gain is not affected by the influence of the on resistances of the analog switches and determined by the ratio of the input resistances and feedback resistances. Consequently, the variance in on resistance due to the variance of the process and the gain error due to variation in on resistance with temperature are reduced.

Description

【発明の詳細な説明】 産業上の利用分野 本発明は、ゲイン誤差の低減と、ＣＭＯＳアナログスイ
ッチのトランジスタサイズの縮小化を図ったゲイン可変
増幅器に関するものである。DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a variable gain amplifier that reduces gain errors and reduces the transistor size of a CMOS analog switch.

従来の技術 従来のこの種のゲイン可変の反転増幅器の構成は、第２
図であった。第２図において、Ｒｇｌ＃”ｌ１２は入力
抵抗、Ｒｆ、、Ｒｆ２　は帰還抵抗、ｓｗ、。2. Description of the Related Art The conventional configuration of this type of variable gain inverting amplifier is
It was a diagram. In FIG. 2, Rgl#"l12 is an input resistance, Rf, and Rf2 is a feedback resistance, sw.

ｓｗ２．ｓｗ、、ｓｗ４はアナログスイッチでオン抵抗
は全てＲｏである。この反転増幅器のゲインは、−（帰
還抵抗値／入力抵抗値）で与えられ、例えば半導体集積
回路に応用されている。sw2. sw, , sw4 are analog switches, and their on resistances are all Ro. The gain of this inverting amplifier is given by -(feedback resistance value/input resistance value), and is applied to, for example, semiconductor integrated circuits.

発明が解決しようとする問題点 このような従来の構成では、例えば、ＳＷ、。The problem that the invention aims to solve In such a conventional configuration, for example, SW.

ＳＷ２がオンしている場合、ゲインは−（Ｒ７，＋ｎ　
ｏ　／ｎ　ｓ　＋　＋　ＲＯ）となる。プロセスバラツ
キや温度変化によるＲｏの変動を小さくしゲイン誤差を
小さくするためには、Ｒ０＜　Ｒｆ、　、　Ｒ、、とし
なければならない。そのために、アナログスイッチのオ
ン抵抗を下げること、すなわち、トランジスタサイズを
大きくしなければならず、面積が大きくなるという問題
点があった。When SW2 is on, the gain is -(R7, +n
o /n s + + RO). In order to reduce fluctuations in Ro due to process variations and temperature changes and to reduce gain errors, it is necessary to satisfy R0<Rf, , R, . For this purpose, it is necessary to lower the on-resistance of the analog switch, that is, to increase the transistor size, which poses a problem of increasing the area.

本発明はこのような問題点を解決するもので、アナログ
スイッチのトランジスタサイズを小さくし、かつ、プロ
セスバラツキや、温度変化によるゲイン誤差を小さくす
ることを目的とするものである。The present invention is intended to solve these problems, and aims to reduce the transistor size of an analog switch and reduce gain errors due to process variations and temperature changes.

問題点を解決するための手段 この問題点を解決するために本発明は、入力抵抗および
帰還抵抗を切り換えるアナログスイッチのオン抵抗が切
り換え抵抗の抵抗値に比例するようにしたものである。Means for Solving the Problem In order to solve this problem, the present invention is such that the on-resistance of the analog switch that switches between the input resistance and the feedback resistance is proportional to the resistance value of the switching resistance.

作用 この構成により、アナログスイッチのオン抵抗を切り換
え抵抗に比べ充分小さくする必要はなく、またトランジ
スタサイズの縮小化と、プロセスのばらつき、温度変化
によるゲイン誤差の減小化が可能となる。Effect: With this configuration, it is not necessary to make the on-resistance of the analog switch sufficiently smaller than the switching resistance, and it is also possible to reduce the transistor size and gain errors due to process variations and temperature changes.

実施例 第１図は本発明の一実施例によるゲイン可変の反転増幅
器の回路図であり、第１図において、１はオペアンプ”
Ｂ、”８２は入力抵抗、Ｒｆｌ、ＦＣｌ２は帰還抵抗、
ｓｗ５．ｓｗ６．ｓｗ、’、ｓｗ８はアナログスイッチ
でオン抵抗をそれぞれＲ６８１１Ｒ０８２’ＲＯｆ＋Ｔ
’Ｏｆ２とし、ｖｉｎは入力端子、ｖｏｕｔは出力端子
である。アナログスイッチのオン抵抗を切り換え抵抗の
α倍（Ｑ＜αく１）とすると、Ｒ＝ａＲ、Ｒ＝ａＲ８２
，ＲＯ１１ ｏｓ＋　　　　　　　　　ｓ＋　　　　　　０８２＝＝
ａＲｆ、ａＲ６ｆ　２＝ａＲｊ”となる。ｓｗ５．ｓｗ
、がオンしている時には、この反転増幅器のゲインは−
（”ｆ＋＋Ｒｏｆ＋／Ｒｓ　＋”ｏｓ、）＝　　（”ｆ
、＋αＲ７、／Ｒ，、＋ａＲ，、）＝−（Ｒ，・、　（
１＋α）／Ｒｓ、（１＋α））＝Ｒ７・１／ＲＩＩとな
り、ゲインはアナログスイッチのオン抵抗の影響を受け
ず、入力抵抗と帰還抵抗の比で決まる。このことから、
プロセスのばらつきによるオン抵抗のばらつき、温度変
化によるオン抵抗の変化によるゲイン誤差を減小させる
ことができ、またオン抵抗を切り換え抵抗の抵抗値に比
べ充分小さくする必要はなく、アナログスイッチのトラ
ンジスタサイズを縮小でき面積を小さくすることができ
る。Embodiment FIG. 1 is a circuit diagram of a variable gain inverting amplifier according to an embodiment of the present invention. In FIG. 1, 1 is an operational amplifier.
B, "82 is the input resistance, Rfl, FCl2 is the feedback resistance,
sw5. sw6. sw,', sw8 are analog switches and their on resistances are R6811R082'ROf+T
'Of2, vin is an input terminal, and vout is an output terminal. If the on-resistance of an analog switch is α times the switching resistance (Q<α×1), then R=aR, R=aR82
,RO11 os+ s+ 082==
aRf, aR6f 2=aRj". sw5.sw
, is on, the gain of this inverting amplifier is −
("f++Rof+/Rs +"os,)= ("f
,+αR7,/R,,+aR,,)=-(R,・, (
1+α)/Rs, (1+α))=R7·1/RII, and the gain is not affected by the on-resistance of the analog switch and is determined by the ratio of the input resistance to the feedback resistance. From this,
Gain errors due to variations in on-resistance due to process variations and changes in on-resistance due to temperature changes can be reduced, and the on-resistance does not need to be sufficiently small compared to the resistance value of the switching resistor, and the transistor size of the analog switch can be reduced. can be reduced and the area can be reduced.

発明の効果 以上のように本発明によれば、ゲイン可変の反転増幅器
のゲインが、アナログスイッチのオン抵抗の影響を小さ
くでき、またアナログスイッチのトランジスタサイズを
小さくでき、その実用的効果は大きい。Effects of the Invention As described above, according to the present invention, the gain of the variable gain inverting amplifier can reduce the influence of the on-resistance of the analog switch, and the transistor size of the analog switch can be reduced, which has great practical effects.

【図面の簡単な説明】[Brief explanation of drawings]

第１図は本発明の実施例におけるゲイン可変の反転増幅
器の電気的結線図、第２図は従来のゲイン可変の反転増
幅器の電気的結線図である。 １・・・・・・オペアンプ、ＳＷ、〜ＳＷ８・・・・・
・アナログスイッチ。 代理人の氏名　弁理士　中　尾　敏　男　ほか１名簿　
１ｆｆｉ ｆ−−１丁アジア１ バｅ３２−帽＆２ ｆ？ｏｆｔ冨ｃＡｉ？４ｆFIG. 1 is an electrical wiring diagram of a variable gain inverting amplifier according to an embodiment of the present invention, and FIG. 2 is an electrical wiring diagram of a conventional variable gain inverting amplifier. 1...Operational amplifier, SW, ~SW8...
・Analog switch. Name of agent: Patent attorney Toshio Nakao and 1 other list
1ffi f--1-cho Asia 1 bar e32-hat &2 f? oftomi? 4f

Claims (1)

【特許請求の範囲】[Claims] オペアンプを用いた反転増幅器において、２種類以上の
入力抵抗をアナログスイッチで切り換え、かつ、２種類
以上の帰還抵抗をＣＭＯＳアナログスイッチで切り換え
、前記入力抵抗および帰還抵抗を切り換える前記アナロ
グスイッチのオン抵抗が切り換え抵抗の抵抗値に比例す
ることを特徴とするゲイン可変増幅器。In an inverting amplifier using an operational amplifier, two or more types of input resistance are switched by an analog switch, and two or more types of feedback resistance are switched by a CMOS analog switch, and the on-resistance of the analog switch that switches the input resistance and the feedback resistance is A variable gain amplifier characterized in that the gain is proportional to the resistance value of a switching resistor.
JP60083762A 1985-04-19 1985-04-19 Variable gain amplifier Granted JPS61242405A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP60083762A JPS61242405A (en) 1985-04-19 1985-04-19 Variable gain amplifier

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP60083762A JPS61242405A (en) 1985-04-19 1985-04-19 Variable gain amplifier

Publications (2)

Publication Number Publication Date
JPS61242405A true JPS61242405A (en) 1986-10-28
JPH0567083B2 JPH0567083B2 (en) 1993-09-24

Family

ID=13811586

Family Applications (1)

Application Number Title Priority Date Filing Date
JP60083762A Granted JPS61242405A (en) 1985-04-19 1985-04-19 Variable gain amplifier

Country Status (1)

Country Link
JP (1) JPS61242405A (en)

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5736896A (en) * 1994-10-21 1998-04-07 Nippondenso Co., Ltd. Signal processing circuit
US5796310A (en) * 1995-12-06 1998-08-18 Denso Corporation Amplification circuit using wire-bonding for adjusting amplification factor
US5854572A (en) * 1996-06-04 1998-12-29 Denso Corporation Compact structure of automatic gain control circuit
US5955919A (en) * 1996-07-26 1999-09-21 Sgs-Thomson Microelectronics Gmbh Nonlinearity compensation in an electric signal processing circuit
JP2007279186A (en) * 2006-04-04 2007-10-25 Nec Electronics Corp Amplifier circuit and driving circuit
WO2010070315A1 (en) * 2008-12-19 2010-06-24 Cambridge Silicon Radio Limited Low distortion amplifier
JP2012244448A (en) * 2011-05-20 2012-12-10 Hitachi Ltd Operational amplification circuit

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5736896A (en) * 1994-10-21 1998-04-07 Nippondenso Co., Ltd. Signal processing circuit
US5796310A (en) * 1995-12-06 1998-08-18 Denso Corporation Amplification circuit using wire-bonding for adjusting amplification factor
US5854572A (en) * 1996-06-04 1998-12-29 Denso Corporation Compact structure of automatic gain control circuit
US5955919A (en) * 1996-07-26 1999-09-21 Sgs-Thomson Microelectronics Gmbh Nonlinearity compensation in an electric signal processing circuit
JP2007279186A (en) * 2006-04-04 2007-10-25 Nec Electronics Corp Amplifier circuit and driving circuit
WO2010070315A1 (en) * 2008-12-19 2010-06-24 Cambridge Silicon Radio Limited Low distortion amplifier
US9184713B2 (en) 2008-12-19 2015-11-10 Qualcomm Technologies International, Ltd. Low distortion amplifier
JP2012244448A (en) * 2011-05-20 2012-12-10 Hitachi Ltd Operational amplification circuit

Also Published As

Publication number Publication date
JPH0567083B2 (en) 1993-09-24

Similar Documents

Publication Publication Date Title
KR920001828A (en) Integral circuit
US7068099B2 (en) Power amplifier module with distortion compensation
JPS61242405A (en) Variable gain amplifier
TW449962B (en) Variable-gain amplifier circuit and attenuator circuit
JPS63150955A (en) Measuring circuit for x-ray ct apparatus
JP3225527B2 (en) Delay circuit
JPH021408B2 (en)
JPS60236509A (en) Differential variable amplifier circuit
JPH0327606A (en) Field effect transistor amplifying circuit
JP2994069B2 (en) Electronic volume circuit
JPH047915A (en) D/a converter
JPS5821210Y2 (en) High frequency integrated circuit device
JPS62111510A (en) Amplifier circuit
JPH01126816A (en) Broad band variable gain amplifier circuit
JP2914011B2 (en) Current switch circuit
JPS639100A (en) Sample holding circuit
JPS61182308A (en) Semiconductor integrated circuit
JPS635290Y2 (en)
JPS62219814A (en) Switching circuit
JPS5896420A (en) Semiconductor switch circuit
JPS6210914A (en) Synthesized reactance device
JPS636956B2 (en)
JPH0380706A (en) Operational amplifier
JPS6041307A (en) Sound signal switching device
JPS616910A (en) Transistor amplifier