收藏本站
参数资料
型号： HCNR200
元件分类： 光电元器件
英文描述： SPECIALTY OPTOELECTRONIC DEVICE
封装： 0.4 INCH, DIP-8
文件页数： 9/19页
文件大小： 415K
代理商： HCNR200
17
toworryabout.However,thesecondcircuitrequirestwo
optocouplers, separate gain adjustments for the posi
tiveandnegativeportionsofthesignal,andcanexhibit
crossoverdistortionnearzerovolts.Thecorrectcircuitto
chooseforanapplicationwoulddependontherequire
ments of that particular application. As with the basic
isolationamplifiercircuitinFigure12a,thecircuitsinFig
ure14aresimplifiedandwouldrequireafewadditional
componentstofunctionproperly.Twoexamplecircuits
thatoperatewithbipolarinputsignalsarediscussedin
thenextsection.
Asafinalexampleofcircuitdesignflexibility,thesimpli
fiedschematicsinFigure15illustratehowtoimplement
420 mA analog currentloop transmitter and receiver
circuitsusingtheHCNR200/201optocoupler.Animpor
tantfeatureofthesecircuitsisthattheloopsideofthe
circuitispoweredentirelybytheloopcurrent,eliminat
ingtheneedforanisolatedpowersupply.
TheinputandoutputcircuitsinFigure15aarethesame
asthenegativeinputandpositiveoutputcircuitsshown
inFigures13cand13b,exceptfortheadditionofR3and
zenerdiodeD1ontheinputsideofthecircuit.D1regu
latesthesupplyvoltagefortheinputamplifier,whileR3
formsacurrentdividerwithR1toscaletheloopcurrent
downfrom20mAtoanappropriatelevelfortheinput
circuit(<50A).
Asinthesimplercircuits,theinputamplifieradjuststhe
LEDcurrentsothatbothofitsinputterminalsareatthe
samevoltage.Theloopcurrentisthendivided
betweenR1andR3.I
PD1isequaltothecurrentinR1and
isgivenbythefollowingequation:
I
PD1=ILOOP*R3/(R1+R3).
Combiningtheaboveequationwiththeequationsused
for Figure 12a yields an overall expression relating the
outputvoltagetotheloopcurrent,
V
OUT/ILOOP=K*(R2*R3)/(R1+R3).
Again,youcanseethattherelationshipisconstant,lin
ear,andindependentofthecharacteristicsoftheLED.
The420mAtransmittercircuitinFigure15bisalittledif
ferentfromthepreviouscircuits,particularlytheoutput
circuit.Theoutputcircuitdoesnotdirectlygeneratean
outputvoltagewhichissensedbyR2,itinsteadusesQ1
togenerateanoutputcurrentwhichflowsthroughR3.
ThisoutputcurrentgeneratesavoltageacrossR3,which
isthensensedbyR2.Ananalysissimilartotheoneabove
yields the following expression relating output current
toinputvoltage:
I
LOOP/VIN=K*(R2+R3)/(R1*R3).
Circuit Design Flexibility
Circuit design with the HCNR200/201 is very flexible
because the LED and both photodiodes are accessible
tothedesigner.Thisallowsthedesignertomakeperf
ormancetradeoffsthatwouldotherwisebedifficultto
make with commercially available isolation amplifiers
(e.g.,bandwidthvs.accuracyvs.cost).Analogisolation
circuitscanbedesignedforapplicationsthathaveeither
unipolar(e.g.,010V)orbipolar(e.g.,±10V)signals,with
positive or negative input or output voltages. Several
simplifiedcircuittopologiesillustratingthedesignflex
ibilityoftheHCNR200/201arediscussedbelow.
ThecircuitinFigure12aisconfiguredtobenoninvert
ingwithpositiveinputandoutputvoltages.Bysimply
changingthepolarityofoneorbothofthephotodiodes,
theLED,ortheopampinputs,itispossibletoimplement
othercircuitconfigurationsaswell.Figure13illustrates
howtochangethebasiccircuittoaccommodateboth
positiveandnegativeinputandoutputvoltages.Thein
putandoutputcircuitscanbematchedtoachieveany
combinationofpositiveandnegativevoltages,allowing
forbothinvertingandnoninvertingcircuits.
All of the configurations described above are unipolar
(singlepolarity);thecircuitscannotaccommodateasig
nalthatmightswingbothpositiveandnegative.Itispos
sible,however,tousetheHCNR200/201optocouplerto
implementabipolarisolationamplifier.Twotopologies
thatallowforbipolaroperationareshowninFigure14.
The circuit in Figure14a uses two current sources to
offsetthesignalsothatitappearstobeunipolartothe
optocoupler.CurrentsourceI
OS1providesenoughoffset
toensurethatI
PD1isalwayspositive.Thesecondcurrent
source,I
OS2,providesanoffsetofoppositepolaritytoob
tainanetcircuitoffsetofzero.CurrentsourcesI
OS1 and
I
OS2canbeimplementedsimplyasresistorsconnectedto
suitablevoltagesources.
ThecircuitinFigure14busestwooptocouplerstoobtain
bipolaroperation.Thefirstoptocouplerhandlesthepos
itive voltage excursions, while the second optocoupler
handlesthenegativeones.Theoutputphotodiodesare
connectedinanantiparallelconfigurationsothatthey
produceoutputsignalsofoppositepolarity.
Thefirstcircuithastheobviousadvantageofrequiring
onlyoneoptocoupler;however,theoffsetperformance
ofthecircuitisdependentonthematchingofI
OS1 and
I
OS2andisalsodependentonthegainoftheoptocoupler.
Changesinthegainoftheoptocouplerwilldirectlyaf
fecttheoffsetofthecircuit.
The offset performance of the second circuit, on the
other hand, is much more stable; it is independent of
optocouplergainandhasnomatchedcurrentsources
相关PDF资料
PDF描述
HCP2HOA16CFREQ TCXO, CLOCK, 0.01 MHz - 160 MHz, HCMOS OUTPUT
ACS6H2A17CFREQ TCXO, CLOCK, 0.01 MHz - 160 MHz, ACMOS OUTPUT
ACS6H2D57CFREQ TCXO, CLOCK, 0.01 MHz - 160 MHz, ACMOS OUTPUT
ACS6H2BB7CFREQ TCXO, CLOCK, 0.01 MHz - 160 MHz, ACMOS OUTPUT
ACS6H2D57BFREQ TCXO, CLOCK, 0.01 MHz - 160 MHz, ACMOS OUTPUT
相关代理商/技术参数
参数描述
HCNR200#050 功能描述:高线性光耦合器 1 Ch 60mW 25mA RoHS:否 制造商:Avago Technologies 输入类型:AC/DC 最大正向二极管电压:1.95 V 最大反向二极管电压:2.5 V 最大输入二极管电流:25 mA 最大功率耗散:60 mW 最大工作温度:+ 100 C 最小工作温度:- 55 C 封装 / 箱体:DIP-8 Gull Wing 封装:Tube
HCNR200#300 功能描述:高线性光耦合器 1 Ch 60mW 25mA RoHS:否 制造商:Avago Technologies 输入类型:AC/DC 最大正向二极管电压:1.95 V 最大反向二极管电压:2.5 V 最大输入二极管电流:25 mA 最大功率耗散:60 mW 最大工作温度:+ 100 C 最小工作温度:- 55 C 封装 / 箱体:DIP-8 Gull Wing 封装:Tube
HCNR-200#300 制造商:Avago Technologies 功能描述:Optocoupler DC-IN 1-CH Linear Photovoltaic DC-OUT 8-Pin PDIP W SMD Tube
HCNR200#350 功能描述:高线性光耦合器 1 Ch 60mW 25mA RoHS:否 制造商:Avago Technologies 输入类型:AC/DC 最大正向二极管电压:1.95 V 最大反向二极管电压:2.5 V 最大输入二极管电流:25 mA 最大功率耗散:60 mW 最大工作温度:+ 100 C 最小工作温度:- 55 C 封装 / 箱体:DIP-8 Gull Wing 封装:Tube
HCNR200#500 功能描述:高线性光耦合器 1 Ch 60mW 25mA RoHS:否 制造商:Avago Technologies 输入类型:AC/DC 最大正向二极管电压:1.95 V 最大反向二极管电压:2.5 V 最大输入二极管电流:25 mA 最大功率耗散:60 mW 最大工作温度:+ 100 C 最小工作温度:- 55 C 封装 / 箱体:DIP-8 Gull Wing 封装:Tube
发布紧急采购，3分钟左右您将得到回复。

采购需求

(若只采购一条型号，填写一行即可)

发布成功！您可以继续发布采购。也可以进入我的后台，查看报价

发布成功！您可以继续发布采购。也可以进入我的后台，查看报价

*型号 *数量 厂商 批号 封装
添加更多采购

我的联系方式

*
*
*