参数资料
| 型号： | SM3E-19.44M |
| 厂商： | Connor-Winfield |
| 文件页数： | 21/36页 |
| 文件大小： | 0K |
| 描述： | IC MOD TIMING 19.440MHZ STRAT 3E |
| 标准包装： | 1 |
| 系列： | SM3 |
| 类型： | 定时模块，系统时钟 |
| PLL： | 是 |
| 主要目的： | 以太网，ADM，DSLAM，SONET/SDH，Stratum，TDM |
| 输入： | LVCMOS |
| 输出： | LVCMOS |
| 电路数： | 1 |
| 比率 - 输入:输出： | 8:3 |
| 差分 - 输入:输出： | 无/无 |
| 频率 - 最大： | 19.44MHz |
| 电源电压： | 3.135 V ~ 3.465 V |
| 工作温度： | 0°C ~ 70°C |
| 安装类型： | 通孔 |
| 封装/外壳： | 32-DIP 模块 |
| 包装： | 管件 |
| 其它名称： | CW643 SM3E 19.44M SM3E19.44M |
第1页第2页第3页第4页第5页第6页第7页第8页第9页第10页第11页第12页第13页第14页第15页第16页第17页第18页第19页第20页当前第21页第22页第23页第24页第25页第26页第27页第28页第29页第30页第31页第32页第33页第34页第35页第36页
SM3E Data Sheet #:
TM054
Page 28 of 36 Rev: 04 Date: 01/26/11
Copyright 2011 The Connor-Winfield Corp. All Rights Reserved
Specifications subject to change without notice
Application Notes continued
Boundary Scan IEEE1149.1-2001 (Limited Testability Support) - Thismoduleexposesaboundaryscanchainwhichcontains
oneormoreboundaryscantestableIEEE1149.1-2001complaintdevices.TheexposedboundaryscanchainisIEEE1149.1-2001
compliant,andsupportsalldocumentedtestingmodesofdevicescontainedwithinchain.Integrationofthismoduleintoanexisting
boundaryscanchainwillrequirethefollowing.
-Substitutionofmodulesfootprintwithprovidedtestabilitymodelschematic.
-Modifiednetlistwillneedtobeloadedintoboundaryscantestvectorgenerationsoftware.
TestabilityModelSchematicandBSDLfile(s)canbeobtaineddirectlyfromfactory.
Control Modes
Thedevicemustbeoperatedinamanualcontrolmode,orautomaticcontrolandreferenceselectionmode.
Reset maybepulledlowforaminimumof10mSduringchipstart-up(oranyotherdesiredtime)toinitializethefulldevicestate.
TheBITSclockoutputfrequencyisselectedbythe
T1/E1pin.WhenT1/E1=1,theBITSfrequencyis1.544MHz,andwhen
T1/E1=0,theBITSfrequencyis2.048MHz.
MASTER SELECT-Determinesthemasterorslavemode.Setto“1”foramaster,and“0”foraslave.Master/slaveswitches
shouldbeperformedwithminimaldelaybetweenswitchingthestatesofeachofthetwodevices.Thiscanbeeasilyaccomplished,for
example,bycontrollingthemaster/slavestatewithasinglesignal,coupledtooneofthedevicesthroughaninverter.
Forsimplexoperation,thedeviceshouldbeinMastermode-set
MASTER SELECTto“1”.
Holdover History Accumulation and Maintenance continued –Wheneverholdoverisentered,itistheActiveHoldoverHistory
thatisusedtodeterminetheholdoverfrequency.TheHistory_Cmdregisterallowstheapplicationtoissuethreeholdoverhistory
controlcommands:
1)SavetheActiveHoldoverHistorytotheBackupHistory.
2)RestoreaBackupHistorytotheActive.
3)FlushtheactiveHistoryaswellastheaccumulationregister.TheBackuphistoryremainsintact.
BoththeActiveandtheBackupholdoverhistoriesareloadedwiththecalibratedfreerunsynthesizercontroldataonreset/power-up.
Theapplicationmightusethe“savetobackup”inasituationwhere,forexample,theprimaryreferenceisknowntobeofhigher
qualitythananysecondaryreferences,inwhichcaseitmaybedesirabletosaveandthenrestoretheholdoverhistoryaccumulated
ontheprimaryreferenceiftheprimaryreferenceislostandholdoverisentereduponlossofasecondaryreference.Userscanrestore
thehistoryfrombackupanytime,evenwhileoperatinginHoldovermode.Thefrequencytransientwillbesmoothandcontinuous.
Itistheresponsibilityofapplicationsoftwaretokeeptrackoftheageandviabilityoftheholdoverbackuphistory.Giventimeand
temperatureeffectsonoscillatoraging,theapplicationmaywishtoperiodicallyperforma“Save”oftheActivehistorytokeepthe
backupcurrent.
Whenswitchingtoanewreference,theactiveholdoverhistorywillremainintactandmarkedas“HoldoverAvailable”(ifitwas
availablebeforethereferenceswitch)untilanewhistoryisaccumulatedonthenewreference(Typically15minutesafterlockhas
beenachieved).Duringthenewhistoryaccumulation,the“HoldoverBuildComplete”bitisreset.Oncethenewhistoryaccumulationis
complete,itistransferredtotheActiveHistoryandthe“HoldoverBuildComplete”bitisset.Theactivehistorywillthencontinuetobe
updatedtotrackthereference.
TheHistory_Policyregisterallowstheapplicationtocontrolhowanewhistoryisbuilt.Whensetto“Rebuild”:
1)Historyaccumulationbeginswhenlockisachievedonthenewreference.
2)Theholdoverhistoryisrebuilt(takingabout15minutes).TheActiveHistoryremainsuntoucheduntilitisreplacedwhenthebuild
iscomplete.
Whenthepolicyissetto“Continue”:
1)Ifthereisno“Available”ActiveHistory,anewbuildoccurs,asunderthe“Rebuild”policy.
2)Ifthereisan“Available”ActiveHistory,itwillcontinue,theaccumulationregisterwillbeloadedfromthe
ActiveHistory,andthe“Build”processisessentiallycompletedimmediatelyfollowinglockonthenewreference.
The“Continue”policymaybeusedbytheapplicationif,forexample,itisknownthatthereferenceswitchedtomaybetracedtothe
samesourceandthereforelikelyhasnofrequencyoffsetfromthepriorreference.Inthatcase,the“Continue”policyavoidsthedelay
ofrebuildingtheholdoverhistory.Iftheswitchislikelytobebetweenreferenceswithknownorunknownfrequencyoffset,thenitis
preferabletousethe“Rebuild”policy.
ThetimesincetheholdoverstatewasenteredmaybereadfromtheHoldover_Timeregister.Valuesarefrom0to255hours,
limitedat255,andresetto0whennotintheholdoverstate.
相关PDF资料 |
PDF描述 |
|---|---|
| SM802104UMG TR | IC SYNTHESIZER 2CH 24-QFN |
| SM802105UMG TR | IC SYNTHESIZER 2CH 24-QFN |
| SM802108UMG | IC SYNTEHSIZER 156.25MHZ 24QFN |
| SM802109UMG TR | IC SYNTHESIZER QUAD 100MHZ 24QFN |
| SM840002KA TR | IC CLK SYNTHESIZER LN 16-TSSOP |
相关代理商/技术参数 |
参数描述 |
|---|---|
| SM3F-100TQ-ACTEL | 功能描述:ADAPTER MODULE 100TQFP RoHS:否 类别:编程器，开发系统 >> 适配器 系列:* 标准包装:96 系列:- 模块/板类型:TQFP 插座模块 适用于相关产品:- |
| SM3F-100VQ-ACT | 制造商:Microsemi Corporation 功能描述:ACTEL VQ100 ADAPTER MODULES |
| SM3F-100VQ-ACTEL | 功能描述:ADAPTER MODULE 100VQFP RoHS:否 类别:编程器，开发系统 >> 适配器 系列:* 标准包装:96 系列:- 模块/板类型:TQFP 插座模块 适用于相关产品:- |
| SM3F-108QN-ACTEL | 功能描述:ADAPTER MODULE 108QFN RoHS:否 类别:编程器，开发系统 >> 适配器 系列:* 标准包装:96 系列:- 模块/板类型:TQFP 插座模块 适用于相关产品:- |
| SM3F-121CS-ACTEL | 功能描述:ADAPTER MODULE 121CSP RoHS:否 类别:编程器，开发系统 >> 适配器 系列:* 标准包装:96 系列:- 模块/板类型:TQFP 插座模块 适用于相关产品:- |
发布紧急采购，3分钟左右您将得到回复。