DS8922AM中文资料

HP8920A综合测试仪使用说明HP8920A/B综合测试仪使用方法一、测试线的连接MAX PWR 60W——仪器射频信号输入输出（注意观察标注的最大功率值，可能有些仪器只能测试5W或者10W的功率）。

接被测试机器的天线头。

（此处不能接错！200mw的那个头不要输入大功率，否则，会损坏仪器！）AUDIO IN （HI）——音频信号输入（接对讲机外接耳机插孔，输入信号后仪器显示相应指标）。

AUDIO OUT——音频信号输出（接对讲机外接话咪插孔，仪器里面模拟出来的音频信号经过话咪插孔进入到对讲机里面进行调制，然后通过仪器显示相关指标）。

其它部分按钮说明：VOLUME：调节仪器蜂鸣器声音大小。

SQUELCH：旋钮上的色点一般调节在中心位置合适，不然，有噪声。

二、测试1、发射测试（检测机器时，一般先测发射，因为发射部分的一些指标不良，会影响到接收）：按仪器面板上的“TX”按键，进入发射指标检测界面。

连接好对讲机各测试线并打开电源，按下对讲机的PTT按键，发射时，主要看仪器屏幕上的三个指标：Tx Frequency ：频率误差（实际发射出来的频率值和该信道标称频率的差值，一般±500Hz即可。

Tx Power：功率大小FM Deviation：最大频偏（一般在4KHz左右，加亚音频之后，会高0.7KHz。

该指标影响对讲机的送话）。

在发射状态下，把仪器的滤波器调小：即把“Filter 1”选择到“＜20Hz”，再把“Filter 2”选择到“300Hz”，即可以在“FM Deviation”这一栏直接查看到该信道所加的模拟亚音频数值。

2、接收测试：按仪器面板上的“RX”按键，在该界面，要设置以下参数：转动面板上的那个大的旋钮，让光标停留在“RF Gen Freq”处，直接按数字键和单位按键，即输入要测试对讲机的接收频率（如458.825MHz），然后，再把光标移到“Amplitude”这一项，分别输入1mv和0.25uv两种场强参数（看你自己的习惯，也可以用“－DBm”的单位），以检测机器的失真度和灵敏度。

用户手册DMC-842数字传声器接口带有线路（Line）输出的8通道数字传声器接口8通道AES转模拟/ADAT接口AES/EBU格式和采样率转换可选的64通道MADI接口24 Bit / 192 kHz数字音频MIDI远程控制重要的安全说明 (4)概述 (5)1. 简介 (6)2. 包装清单 (6)3. 简介及主要特点 (6)4. 首次使用——快速上手 (7)4.1 控制、接口与显示 (7)4.2 快速上手 (9)5. 附件 (9)6. 产品保证 (10)7. 附录 (10)CE / FCC符合性声明 (11)使用和操作 (12)8. 前面板控制 (13)8.1 Select（选择）键和旋钮（SET） (13)8.2 Clock Section（时钟部分） (14)8.3 模拟输出 (14)8.4 Remote（遥控） (15)9. 输入通道 (15)9.1 通用 (15)9.2 Gain（增益） (15)9.3 数字幻象供电 (15)9.4 Mode 2 (16)9.5 Stereo / Inactive (16)9.6 M/S处理 (16)9.7 SRC（采样率转换器） (17)9.8 PAR (17)9.9 Sync (17)10. Setup（设置）菜单 (18)10.1 通用 (18)10.2 ID（Id,自动ID） (18)10.3 Bank（bA,库） (18)10.4 Auto ID（Au,自动ID） (19)10.5 Delay Compensation（dC,延迟补偿） (19)10.6 Follow Clock（FC,跟随时钟） (20)10.7 Word Clock Out（Co,字时钟输出） (20)10.8 Peak Hold（Ph,峰值保持） (20)10.9 Digital Output（do,数字输出） (20)10.10 Analog Output（Ao,模拟输出） (21)10.11 Gain（GA,增益） (21)10.12 Control Pulse（Cp,控制脉冲） (21)10.13 Sync Pulse（SP,同步脉冲） (21)10.14 Special（SPECIAL） (22)11. Parameter（参数）菜单 (22)11.1 通用 (22)11.2 Low Cut（Lo-Cut,低切） (23)11.3 Directivity Pattern（PAttErn,指向性图） (23)11.4 Pre-Attenuation（AttEnuAtIon,预先衰减） (23)11.5 Mute（mute,静音） (23)11.6 Peak Limiter（LImItEr,峰值限制器） (23)11.7 Command Type（ComtyPE,命令类型） (23)12. Remote Control（远程控制） (24)12.1 MIDI (24)12.2 MIDI over MADI（借助MADI的MIDI） (24)12.3 Remote Control Software（远程控制软件） (25)12.4 RS232 (26)输入和输出 (27)13. 数字输入 (28)13.1 XLR (28)13.2 D-Sub - AES/EBU Sync（同步） (28)14. 数字输出 (29)14.1 AES/EBU (29)14.2 ADAT光纤 (30)14.3 I64 MADI卡 (31)14.4不同的MADI系列可配置I64 MADI卡和ADI-642 (32)15. 模拟输出 (33)16. 字时钟 (34)16.1 字时钟输入和输出 (34)16.2 技术描述和使用 (35)16.3 布线和终止 (36)17. MIDI (36)技术参考资料 (37)18. 技术指标 (38)18.1 模拟 (38)18.2 数字输入 (38)18.3 数字输出 (40)18.4 数字 (40)18.5 MIDI (40)18.6 通用 (41)18.7 固件 (41)18.8 MADI用户比特位 (41)18.9 接口针脚 (41)19. 技术背景 (43)19.1 术语 (43)19.2 锁定（Lock）与SyncCheck（同步检查） (44)19.3 延时（Latency）与监听（Monitoring） (45)19.4 DS –双倍速 (46)19.5 QS –四倍速 (46)19.6 AES/EBU - SPDIF (47)19.7 MADI基础 (48)19.8 SteadyClock（稳定时钟） (49)20. 框图 (50)21. DMC-842的MIDI实现 (51)21.1 基本SysEx格式 (51)21.2 通知类型–命令 (51)21.3 表格 (53)重要的安全说明注意! 不要打开底盘，以防触电。

Agilent8922MGSM\CDMA手机综合测试仪产品型号: 综合测试仪Agilent8922M产品说明与介绍8922GSM测试装置8922GSM测试装置可以理想地用于R&D、高层维护服务和生产制造方面。

易于使用、丰富而灵活的功能特性使它成为实验台工作选择的仪器。

8922的速度、准确度和重复度使它能够理想地用于来货输入检验和大量生产方面。

8922包括一个GSM基站仿真器及所有信令和测量的能力，能够全面地测试移动台而无需任何附加设备。

GSM无线电测试解决方案8922是一套完整的测试GSM无线台射频部分的测量仪器。

除了频率易变的0.3GMSK 射频发生器外，RF分析仪还有灵活的本地振荡器、相关数据解调节器、脉冲解调器、调频解调器、用于分析相位和频率误差的综合方法分析仪、合成频谱分析仪和脉冲功率计。

8922增加了一个用于完成GSM接收机测量、信道CODEC和呼叫控制协议的误码率测试仪（BERT），以便在进行测量的同时建立电话呼叫并保持链路。

通过用于移动台功能测试的声频CODEC简化了回波模式，并且利用电气人机接口（EMMI）来控制移动台和支持数字音频接口（DAI）。

8922中的快速存储器易于升级。

GSM 数据和HSCSD 测试解决方案8922支持测试GSM单时隙数据和高速电路交换数（HSCSD）移动台的能力。

用在R&D、生产和维修方面，选件K09、K17和K18能够测试单时隙、2x1、2x2、9.6Kb/s和14.4Kb/s 移动数据装置。

完整的成套工具除了完整配套的GSM测量之外，Agilent 8922还包括对于模块测试、排除故障以及调谐作业等有效的通用工具。

这些工具包括一台数字示波器、CW RF合成器、频谱分析仪、CW RF频率计数器、CW和峰值RF功率计、交流电压表、直流电压表、1kHz失真/SINAD（信号对噪声和失真比）测试仪、音频频率计和合成声源。

这些功能的组合使8922对于GSM无线设备的制造和修理都是极为有效的工具。

FLUKE 8922A8920A, 8921A & 8922AAutorangingFluke's autoranging feature allows you to carry out your testing without having to change ranges manually. A range can be placed on HOLD or manually stepped up to a higher range. On HOLD, the meter will remain in a given range regardless of changes in input lev­els. On STEP UP, the meter will increase ranges step-by-step until the switch is released. Peaking/Dipping MeterIn addition to an accurate digital display, all Fluke Voltmeters in the 8920-Series feature an analog meter for peak and null voltage adjust­ments. The meter indicates O to 100 percent full scale in each range.Linear Analog OutputModels 8920A and 8922A are equipped with a rear panel output for driving X-Y or st d p chart recorders, delivering voltages proportional to the display count. A 2-volt level equals 2000 counts, a 1-volt level equals 1000 counts, etc. This feature is not available on Model 8921A. AccuracyFluke Digital Voltmeters avoid the possibili­ties for error so common in analog meters. The digital displays eliminate the likelihood of mis­reading the meter due to viewing angle prob­lems of parallax common with analog meters. Also, the accuracy of 8920-Series Voltmeters is specified as a percent of reading rather than as percent of full scale.Percent of reading accuracy does not de­grade for measurements at the low end of a scale. Front panel switching offers a choice of readings in dB or volts.Technical SpecificationsThe a ccuracy s pecifications b elow apply from 9% to 100% of full scale and from 18°C to 28°C for 90 days. For six-month specifications multi­ply figures by 1.5.AC Accuracy: ± % of voltage reading or ±dB (8920A/8921 A)Range 2Hz 10 H z 20Hz 50Hz 10 kHz 700V200V1%or 0.5%or 20V 0.15dB 0.1 dB 2V Not200mV Speci-5%orlied 0.5dB 2%or 1%or 20 m V 0.25 d B 0.15dB3%or 2%or 2mV0.35dB 0.25dBAC Accuracy: ± % of voltage reading or ±dB(8922A)Range 2Hz 10 H z 20Hz 50Hz 10 k HzFILTER IN I700V200V 1%or•0.15 d B 1%or 0.5%or20V 0.15 d B 0.1 d B2V 5%or200 mV 3%or• 0.5dB0.35dB2%or•0.25dB 2%or 1%or20 mV 0.25 d B 0.15 d B5%or0.5dB5%or• 5%or 3%or 2%or I2 mv0.5 d B .. 0.5dB 0.35 d B 0.25dB• Valid when AC + DC DAMPING is selected andinput has no de components.••Below 2 mV add number of digits (N) to ±5% volt­age readings, where N = 5 + mV input. Or, for dBreadings. add N to ±0.5 dB, where N = 0.5 + (mVinput)2AC+DC Accuracy: Add to AC accuracy specifi­cations (above) ±10 digits or ±0.5 dB above 2mV, or ±100 digits or ±5.0 dB below 2 mV. Forde only, add above digits to 50 Hz to 10 kHzspecificationsFunctions: True RMS measurements only. ACor AC+ DC (8920A and 8921 A); AC or AC+ DCwith damping (8922A)Maximum Input: 700V rms or 1 O OOV peak, not toexceed a volt-hertz product of 1 x 108 on anyrangeMaximum Common Mode Voltage8920A and 8922A: 400 mV rms or 600 mVpeak8921A: 500V rms or 700V peakAC Common Mode Rejection: �60 dB at 50 and60 Hz with 1000 unbalanceDC Common Mode Rejection: �100 dB, 1000unbalanceCrest Factor: 7 at full scale, increasing downscale by 7 times the voltage range divided by thevoltage input. Degrades below 10 Hz, annun­ciated when capability exceeded (8922A only)Input Impedance: 10 MO shunted by <30 pF200kHz 1 MHz 2MHz 10 M Hz 20MHzNot Specified0.7%or0.15 d B3% o r0.35 d B 5%or0.5dB2%or0.25dB 4%or0.4dB I3%or0.35dB200kHz 1 MHz 2MHz 11 MHzFILTER OUTNot Specified0.7%or0.15 d B3%or0.35 d B2%or 5%or0.25 d B 0.5dB4% o r0.4 d BVoltage R11nges: 2 mV, 20 mV, 200 mV, 2V, 20V,200V, 700VRanging: Autoranging with HOLD to defeat a�to•ranging and STEP UP for manual ranging.Ranges up at 2000 counts and ranges down at180 countsDecibel Ranges: In the autorange mode, theinstrument appears as though it has a singlerange spanning 131 dBdBm Reference: Twelve user-selectable impe­dances are provided to reference a O dBm, 1mW level (500,750,930, 1100, 1240, 1350,1500, 3000, 6000, 9000, 10000, and 12000)(dBV = 10000)Relative dB Reference: A voltage input presentwhen this button is pushed is held as "O dB"reference point. Subsequent readings indicate±deviations from this pointVoltage Resolution: 0.05% of ranges (3½ digits)Decibel Resolution: O.Q1 dB (4½ digits)Typical-3 dB Points: 40 MHz on 20 mV thru 20Vranges and 4 MHz on 2 mV range (8920A/8921 A); 22 MHz on 2 mV to 20V ranges (8922A)Low Pass Filter: Approximately 200 kHz -3 dBpoint, on 8922A onlyReading Rate: 2.5/s or 1 /s with ac + de withdamping (8922A)Autorange Rate: <950 ms or <3.5s with ac + dewith damping (8922A)Response Time: (To rated accuracy) <1.6s or<7s with ac + de with damping (8922A)Readout: Panel-select able for volts or dB,auto•matic decimal point location: analog peaking/dipping meter. " V .. "V .. "dB,,LED Annunciators: Indicate m , ,"REL REF," and "2 MHz MAX" for 2 mV range(8920A and 8921A) and "UNCAL" when crestfactor limitation exceeded (8922A)Overrange: Flashes maximum reading for thatrangeUnderrange: Flashes decimalLinear Analog Output: (8920A and 8922A only)Linear output of 2000 mV de for a 2000-countreadout; ±1.0% relative to display; essentiallyoo output into a �10 kO load; non-isolated, withoutput common same as input common。

DS8922/DS8922A/DS8923A TRI-STATE ®RS-422Dual Differential Line Driver and Receiver PairsGeneral DescriptionThe DS8922/22A and DS8923A are Dual Differential Line Driver and Receiver pairs.These devices are designed spe-cifically for applications meeting the ST506,ST412and ESDI Disk Drive Standards.In addition,the devices meet the requirements of the EIA Standard RS-422.These devices offer an input sensitivity of 200mV over a ±7V common mode operating range.Hysteresis is incorpo-rated (typically 70mV)to improve noise margin for slowly changing input waveforms.An input fail-safe circuit is pro-vided such that if the receiver inputs are open the output as-sumes the logical one state.The DS8922A and DS8923A drivers are designed to provide unipolar differential drive to twisted pair or parallel wire trans-mission plementary outputs are logically ANDed and provide an output skew of 0.5ns (typ.)with propagation delays of 12ns.Both devices feature TRI-STATE outputs.The DS8922/22A have independent control functions common to a driver and receiver pair.The DS8923A has separate driver and receiver control functions.Power up/down circuitry is featured which will TRI-STATE the outputs and prevent erroneous glitches on the transmis-sion lines during system power up or power down operation.The DS8922/22A and DS8923A are designed to be compat-ible with TTL and CMOS.Featuresn 12ns typical propagation delay n Output skew —±0.5ns typicaln Meets the requirements of EIA Standard RS-422n Complementary Driver Outputsn High differential or common-mode input voltage ranges of ±7Vn ±0.2V receiver sensitivity over the input voltage range n Receiver input fail-safe circuitryn Receiver input hysteresis —70mV typical n Glitch free power up/down nTRI-STATE outputsConnection DiagramsTRI-STATE ®is a registered trademark of National Semiconductor Corp.DS8922A Dual-In-LineDS008511-1Order Number DS8922M,DS8922N,DS8922AM or DS8922ANSee NS Package Number M16A or N16EJune 1998DS8922/DS8922A/DS8923A TRI-STATE RS-422Dual Differential Line Driver and Receiver Pairs©1998National Semiconductor Corporation Connection Diagrams(Continued)Truth Tables DS8922/22AEN1EN2RO1RO2DO1DO200ACTIVE ACTIVE ACTIVE ACTIVE 10HI-Z ACTIVE HI-Z ACTIVE 01ACTIVE HI-Z ACTIVE HI-Z 11HI-ZHI-ZHI-ZHI-ZDS8923ADEN REN RO1RO2DO1DO200ACTIVE ACTIVE ACTIVE ACTIVE 10ACTIVE ACTIVE HI-Z HI-Z 01HI-Z HI-Z ACTIVE ACTIVE 11HI-ZHI-ZHI-ZHI-ZDS8923A Dual-In-LineDS008511-2Order Number DS8923AM,DS8923AN,See NS Package Number M16A or N16E 2Absolute Maximum Ratings(Note1)If Military/Aerospace specified devices are required, please contact the National Semiconductor Sales Office/ Distributors for availability and specifications.Supply Voltage7V Drive Input Voltage−0.5V to+7V Output Voltage 5.5V Receiver Output Sink Current50mA Receiver Input Voltage±10V Differential Input Voltage±12V Maximum Package Power Dissipation@+25˚CM Package1300mWN Package1450mW Derate M Package10.4mW/˚C above+25˚CDerate N Package11.6mW/˚C above+25˚CStorage Temperature Range−65˚C to+165˚C Lead Temp.(Soldering,4seconds)260˚CRecommended Operating ConditionsMin Max Units Supply Voltage 4.5 5.5V Temperature(T A)070˚CDS8922/22A and DS8923A Electrical Characteristics(Notes2,3,4) Symbol Conditions Min Typ Max Units RECEIVERV TH−7V≤V CM≤+7V−200±35+200mVV HYST−7V≤V CM≤+7V1570mVR IN V IN=−7V,+7V(Other Input=GND) 4.0 6.0kΩI IN V IN=10V 3.25mAV IN=−10V−3.25mAV OH V CC=MIN,I OH=−400µA 2.5VV OL V CC=MAX,I OL=8mA0.5VI SC V CC=MAX,V OUT=0V−15−100mA DRIVERV OH V CC=MIN,I OH=−20mA 2.5VV OL V CC=MIN,I OL=+20mA0.5VI OFF V CC=0V,V OUT=5.5V100µA|VT|–|VT|0.4VVT 2.0V|V OS–V OS|0.4VI SC V CC=MAX,V OUT=0V−30−150mA DRIVER and RECEIVERI OZ V OUT=2.5V50µATRI-STATE V CC=MAX V OUT=0.4V−50µA LeakageI CC V CC=MAX ACTIVE76mATRI-STATE78mA DRIVER and ENABLE INPUTSV IH 2.0VV IL0.8VI IL V CC=MAX,V IN=0.4V−40−200µAI IH V CC=MAX,V IN=2.7V20µAI I V CC=MAX,V IN=7.0V100µAV CL V CC=MIN,I IN=−18mA−1.5V3Receiver Switching Characteristics(Figures1,2,3)Parameter Conditions Min Typ Max Units89228922A/23A T pLH CL=30pF1222.520ns T pHL CL=30pF1222.520ns |T pLH–T pHL|CL=30pF0.55 3.5ns Skew(Channel to Channel)CL=30pF0.5 3.0 2.0ns T pLZ CL=15pF S2Open15ns T pHZ CL=15pF S1Open15ns T pZL CL=30pF S2Open20ns T pZH CL=30pF S1Open20nsDriver Switching CharacteristicsParameter Conditions Min Typ Max Units89228922A/23A SINGLE ENDED CHARACTERISTICS(Figures4,5,6,8)T pLH CL=30pF121515ns T pHL CL=30pF121515ns T TLH CL=30pF51010ns T THL CL=30pF51010ns |T pLH–T pHL|CL=30pF0.5ns Skew CL=30pF(Note5)0.55 3.5ns Skew(Channel to Channel)0.5 3.0 2.0ns T pLZ CL=30pF15ns T pHZ CL=30pF15ns T pZL CL=30pF20ns T pZH CL=30pF20ns DIFFERENTIAL SWITCHING CHARACTERISTICS(Note6),(Figure4)T pLH CL=30pF121515ns T pHL CL=30pF121515ns |T pLH–T pHL|CL=30pF0.5 6.0 2.75ns Note1:“Absolute Maximum Ratings”are those values beyond which the safety of the device cannot be guaranteed.They are not meant to imply that the device should be operated at these limits.The Table of“Electrical Characteristics”provides conditions for actual device operation.Note2:All currents into device pins are shown as positive values;all currents out of the device are shown as negative;all voltages are referenced to ground unless otherwise specified.All values shown as max or min are classified on absolute value basis.Note3:All typical values are V CC=5V,T A=25˚C.Note4:Only one output at a time should be shorted.Note5:Difference between complementary outputs at the50%point.Note6:Differential Delays are defined as calculated results from single ended rise and fall time measurements.This approach in establishing AC performance specifications has been taken due to limitations of available Automatic Test Equipment(ATE).The calculated ATE results assume a linear transition between measurement points and are a result of the following equations:Where:Tcp=Crossing PointTra,Trb,Tfa and Tfb are time measurements with respect to the input.4Switching Time WaveformsDS008511-3AC Test Circuits and Switching WaveformsDS008511-4FIGURE1.DS008511-5FIGURE2.5AC Test Circuits and Switching Waveforms(Continued)DS008511-6S1S2S3T PLZ Closed Open+2.5VT PHZ Open Closed−2.5VT PZL Closed Open+2.5VT PZH Open Closed−2.5VFIGURE3.DS008511-7FIGURE4.DS008511-8FIGURE5.DS008511-9FIGURE6.6AC Test Circuits and Switching Waveforms(Continued)Typical Performance Characteristics(DS8923A)DS008511-10FIGURE 7.DS008511-13FIGURE 8.Driver V OH vs I OH vs TemperatureDS008511-14Driver V OH vs I OH vs V CCDS008511-15Driver V OL vs I OL vs TemperatureDS008511-16Driver V OL vs I OL vs V CCDS008511-177Typical Performance Characteristics(DS8923A)(Continued)Receiver V OH vs I OH vs TemperatureDS008511-18Receiver V OH vs I OH vs V CCDS008511-19Receiver V OL vs I OL vs TemperatureDS008511-20Receiver V OL vs I OL vs V CCDS008511-21Driver Differential Propagation Delay vs TemperatureDS008511-22Driver Differential Propagation Delay vs V CCDS008511-23 8Typical Performance Characteristics(DS8923A)(Continued)Receiver PropagationDelay vs TemperatureDS008511-24Receiver PropagationDelay vs V CCDS008511-25Driver V OD vs TemperatureDS008511-26Driver V OD vs V CCDS008511-27Driver V OD vs R LDS008511-28Driver Differential TransitionTime vs TemperatureDS008511-29 9Typical Performance Characteristics(DS8923A)(Continued)Driver Differential Transition Time vs V CCDS008511-30Supply Current vs TemperatureDS008511-31Supply Current vs VCCDS008511-32I CC vs Driver Switching FrequencyDS008511-33Driver Short Circuit Current vs Temperature DS008511-34Driver Short Circuit Current vs V CCDS008511-35 10Typical Performance Characteristics(DS8923A)(Continued)Typical ApplicationsReceiver Short Circuit Current vs TemperatureDS008511-36Receiver Short Circuit Current vs V CCDS008511-37ESDI ApplicationDS008511-1111Typical Applications(Continued)ST504and ST412ApplicationsDS008511-12 12Physical Dimensions inches(millimeters)unless otherwise notedSO Package(M)Order Number DS8922M,DS8922AM,or DS8923AMNS Package Number M16AMolded Dual-In-Line Package(N)Order Number DS8922N,DS8922AN,or DS8923ANNS Package Number N16E13LIFE SUPPORT POLICYNATIONAL’S PRODUCTS ARE NOT AUTHORIZED FOR USE AS CRITICAL COMPONENTS IN LIFE SUPPORT DE-VICES OR SYSTEMS WITHOUT THE EXPRESS WRITTEN APPROVAL OF THE PRESIDENT OF NATIONAL SEMI-CONDUCTOR CORPORATION.As used herein:1.Life support devices or systems are devices or sys-tems which,(a)are intended for surgical implant intothe body,or (b)support or sustain life,and whose fail-ure to perform when properly used in accordancewith instructions for use provided in the labeling,can be reasonably expected to result in a significant injury to the user.2.A critical component in any component of a life support device or system whose failure to perform can be rea-sonably expected to cause the failure of the life support device or system,or to affect its safety or effectiveness.National Semiconductor Corporation AmericasTel:1-800-272-9959Fax:1-800-737-7018Email:support@National Semiconductor EuropeFax:+49(0)180-5308586Email:europe.support@Deutsch Tel:+49(0)180-5308585English Tel:+49(0)180-5327832Français Tel:+49(0)180-5329358Italiano Tel:+49(0)180-5341680National Semiconductor Asia Pacific Customer Response Group Tel:65-2544466Fax:65-2504466Email:sea.support@National Semiconductor Japan Ltd.Tel:81-3-5620-6175Fax:81-3-5620-6179D S 8922/D S 8922A /D S 8923A T R I -S T A TE R S -422D u a l D i f f e r e n t i a l L i n e D r i v e r a n d R e c e i v e r P a i r sNational does not assume any responsibility for use of any circuitry described,no circuit patent licenses are implied and National reserves the right at any time without notice to change said circuitry and specifications.。

DIGITAL SOUND METER WITH JUMBO DISPLAY USER’S MANUALDSM8925Please read this manual carefully and thoroughlybefore using this product.TABLE OF CONTENTS Introduction . . . . . . . . . . . . . . . . . . . . . .3 Key Features . . . . . . . . . . . . . . . . . . . . .4 What’s in the Box . . . . . . . . . . . . . . . . .5 Product Overview . . . . . . . . . . . . . .5 –7 Setup Instructions . . . . . . . . . . . . . . . . .8 Install Batteries . . . . . . . . . . . . . . . .8 Operating Instructions . . . . . . . . .8 –15 Making Basic Measurements . .8 –9 Autoranging vs.Manual Ranging . . . . . . . . . . .9 –11 Time and FrequencyWeighting Options . . . . . . . . .11 –12 Storing and RecallingMIN and MAX Readings . . . .12 –13 Operating inMAX HOLD mode . . . . . . . . . .13 –14 Disabling Auto Power Off . . . . . . .14 Calibrating the Meter . . . . . . . . . .15 Specifications . . . . . . . . . . . . . . . . . . .16 Maintenance Tips . . . . . . . . . . . . . . . .17 Warranty Information . . . . . . . . . .17 –18 Return for Repair Policy . . . . . . . . . . .182INTRODUCTIONThank you for purchasing General Tools & Instruments’ DSM8925 Digital Sound Meter with Jumbo Display. Please read this user’s manual carefully and thoroughly before using the instrument.The DSM8925 uses an integrated condenser microphone to measure the noise level of an environment or the loudness of a machine, typically in order to comply with health and/or safety rules. The meter has a range of 30 to 130 dB and an accuracy of ±2 dB. Real-time measurements are shown within a backlit liquid-crystal display window in two forms: as a three- or four-digit number, and as a line on an analog bar graph.Several features improve the meter’s versatility. Among them are two user-selectable operating modes: “A” or “C”frequency weighting, and fast or slow time response. Users also can override autoranging (the default mode) and manually select a fixed measurement range, improving the meter’s response time and measurement resolution. The meter can display the minimum and maximum sound levels measured during a recording session, as well as hold a maximum level on-screen until it is exceeded.3Physical features of the DSM8925 include an analog output jack for connecting to a data logger or chart recorder, a tripod mounting socket, and an adjustment screw for calibrating the meter to a standard 94 dB input.The DSM8925 includes a wind shield ball and is powered by four “AAA” batteries (also included).KEY FEATURES• Measures sound level of a machineor an environment• Jumbo LCD is easy to read• “A” or “C” frequency weighting• Fast or slow time weighting• Autoranging or manual ranging• Displays maximum and minimum readings • Max reading can be held until exceeded • Auto power off• Analog output for data logging• Calibrates to standard 94dB signal• Tripod mount socket on back• Includes wind shield ball• Powered by four “AAA” batteries4WHAT’S IN THE BOXThe DSM8925 comes fully assembled in a box along with a wind shield ball, four “AAA”batteries and this user’s manual.PRODUCT OVERVIEW Figure 1 shows all of the controls, indicators and connectors on the front and right side of the DSM8925. Familiarize yourself with their positions and functions before moving on to the setup procedure.1. The DSM8925’s controls, indicators and connectorsA.Wind shield ballB.MicrophoneC.Liquid-crystal displayD.Power on/off buttonE.A/C —Selects “A” or “C” frequencyweighting 5EF FRONTF.REC—Enters/exits Recording modeG.RNG—Selects autoranging or manualrangingH.F/S—Selects fast or slow time responseI.MAX HOLD buttonJ.Calibration adjustment screwK.Analog output jackFigure 2 shows all text and icons that could appear in the display window at various times.2. All possible display indications and their meaningsREC Meter is in Recording mode, trackingmaximum and minimum sound levelmeasurementsMAX Digital readout is highest levelrecorded since entering RecordingmodeMIN Digital readout is lowest levelrecorded since entering RecordingmodeMAX HOLD Meter is in Max Hold mode. Digitalreadout is highest level measuredsince entering this mode6FAST Meter is applying fast time weightingto inputsSLOW Meter is applying slow time weighting to inputsAUTO Meter is automatically choosingmeasurement range with bestresolutionMANU Meter is using user-selectedmeasurement rangeBA Reserved for future useSPL Abbreviation of sound pressure level(the parameter measured)Meter’s battery is very low on charge Array and should be replacedA Meter is applying “A” frequencyweighting to inputsC Meter is applying “C” frequencyweighting to inputsdB Sound level unit (accompaniesreading at its left)40Range Baseline (low end of currentmeasurement range, in dB). “40”indicates 40 to 70 dB range; otherpossible numbers in this displayposition are 60 (for 60 to 90 dBrange), 80 (for 80 to 110 dB range)and 100 (for 100 to 130 dB range)+0, +10,Labels of analog bar graph scale.+20, +30Indicate amplitude of input (in dB)relative to Range Baseline above leftend of graph7SETUP INSTRUCTIONS INSTALL FOUR BATTERIESThe meter’s battery compartment is accessible from the back of the unit. Use a Philips-head screwdriver to remove the one screw holding the cover in place. Then install the four included “AAA” batteries so their + and – ends match the images stenciled inside the compartment. Finally, replace the cover and secure it with the Philips-head screw. OPERATING INSTRUCTIONSMAKING BASIC MEASUREMENTSTo begin, press the button to power on the meter. The display will take a few seconds to stabilize and then begin reading out real-time sound level measurements.Note how the digital numbers and the readings from the analog bar graph track each other. At times, the two displays may seem slightly out of sync—and they are, because they refresh at different rates.Also note how the number above the left end of the bar graph—the Range Baseline—changes each time a much louder or softer sound is heard. Each change confirms that the meter is operating in Autoranging mode. To demonstrate that autoranging is on in a quiet environment, rub the windscreen with your hand (to simulate a loud noise) and watch the Range Baseline change to 100.8To measure the loudness of a sound source, point the microphone at it.The meter’s default settings are autoranging on (enabling measurements from 30 to 130 dB), fast time weighting and “A” frequency weighting. When the meter is powered on, AUTO will appear on the left side of the display, with FAST on the top line and A on the right side. Following are procedures for changing each of these settings to suit the application.AUTORANGING VS.MANUAL RANGINGThe DSM8925 has four measurement ranges: 40 to 70 dB, 60 to 90 dB, 80 to 110 dB, and 100 to 130 dB. When the meter is powered on, it automatically enters Autoranging mode. In this mode, it automatically switches to the range that displays the input with the finest resolution. For example, the meter could display a sound level of 65 dB using either the 40 to 70 dB or the 60 to 90 dB range. In autoranging mode, it would choose the lower of the two ranges (40 to 70 dB) because on this scale 65 dB has a better (finer) measurement resolution.If you already know the loudness range of the machine or environment you wish to measure, and that range is limited, consider exiting autoranging mode and operating the meter in only one of those four fixed ranges. The benefit of operating the meter in this mode—called Manual Ranging mode—is speed.9The meter can display its results more quickly because it does not have to first determine which range to use.To exit Autoranging Mode and enter Manual Ranging mode, briefly press the RNG button on the front panel. Note that when you press the button, the text MANU replaces AUTO on the left side of the display. Also note that the Range Baseline above the left end of the bar graph no longer changes in response to louder or softer sounds, as in did in Autoranging mode.When the RNG button is pressed, the meter randomly chooses one of the four ranges. Accordingly, the first Range Baseline number displayed could be 40, 60, 80 or 100. For the highest display resolution, the low end of the range you choose should be just below the quietest sound you expect to hear. For example, if your target normally produces sound levels between 85 and 105 dB, you should manually choose the 80 to 110 dB range.To manually select a specific measurement range, briefly press the RNG button as many times as necessary until its Range Baseline number appears above the left end of the analog bar graph. Each press of the RNG button advances the Range Baseline number by 20 dB; after 100, it returns to 40.Note that in Manual Ranging mode, whenever a sound level is outside the chosen range the 10digital display will show the letters LO or HI. If this happens often, consider switching back to Autoranging mode.To exit Manual Ranging mode and return to Autoranging Mode, press and hold the RNG button until the text AUTO replaces MANU on the left side of the display.TIME AND FREQUENCY WEIGHTING OPTIONSYou can choose Fast or Slow response time and “A” or “C” frequency weighting to suit different applications.By default, when the meter is powered on it begins operating with fast time weighting (a fast integration time constant) and “A”frequency weighting. Fast time weighting, with a response time of 200 milliseconds, simulates the response time of the human ear and is better for measuring the volume of singular events. Slow weighting, with a response time of 500 ms, is a better choice for measuring the average sound level that an ongoing process (such as machine vibration) produces over time.To switch the meter’s response time from fast to slow, press the F/S button. The word on the right side of top line of the display will change from FAST to SLOW. To return to fast time weighting, press the F/S button again. As mentioned earlier, when the DSM8925 is powered on it begins operating with “A”frequency weighting. The shape of the “A”11curve simulates the response of the human ear, and is therefore the better choice for measuring the sound level of an environment for the purpose of regulatory compliance, workplace design or noise-pollution control. By comparison, the “C” weighting curve is flatter, and is therefore better for measuring the sound level of a piece of machinery. In the U.S., most OSHA-mandated sound level measurements are made by instruments set for slow response and “A” frequency weighting.To switch from “A” frequency weighting to “C” weighting, press the A/C button. The letter at the right of the display will change from A to C. To switch back to “A” frequency weighting, press the A/C button again. STORING AND RECALLINGMIN AND MAX READINGSThe DSM8925 can also operate in “Recording” mode, for the purpose of tracking and displaying minimum and maximum sound level measurements.To enter Recording mode, press the REC button briefly. The text REC will appear at the upper left of the display.To display the minimum sound level measured since entering Recording mode, press the REC button briefly again. The text MIN will appear on the top line of the display and the digital display will indicate the lowest sound volume measured during this recording 12session. While the digital display is showing the minimum sound value, the meter continues to measure real-time sound level inputs and to display its results on the analog bar graph.To display the maximum sound level measured since entering Recording mode, press the REC button briefly one more time. The text MAX will replace MIN on the top line of the display and the digital display will indicate the highest sound volume measured during this recording session. While the digital display is showing the maximum sound value, the meter continues to measure real-time sound level inputs and to display its results on the analog bar graph.To repeat the process, press and hold the REC button briefly. This does not begin a new recording session. It simply extends the duration of the current session.To exit Recording mode, press and hold the REC button until the text REC disappears from the top line of the display.OPERATING IN MAX HOLD MODE You may want to use the meter’s digital display to show the loudest sound level measured up to a certain point in time. In this operating mode—called MAX HOLD mode—the digital display shows and holds the loudest sound level received since entering that mode. The analog bar graph continues to display measured input levels in real time.13However, the digital display is updated only when the meter detects a louder sound.To enter MAX HOLD mode, press the MAX HOLD button at the lower right of the front panel. To exit this mode, press the MAX HOLD button againDISABLING AUTO POWER OFFBy default, the meter powers off automatically after 20 minutes to avoid discharging the batteries. However, you can disable this feature if you would like to track sound levels over a longer period of time. For this purpose, you will also need to feed the meter’s analog output signal (available via a jack on the right side of the unit) into a chart recorder or data logger.To disable Auto Power Off, first power off the meter by pressing the button. Then power on the meter in a special way by pressing the button and pressing and holding the MAX HOLD button at the same time. This will cause the letter “n” to appear briefly on the digital display. Once “n” has appeared, you can release the MAX HOLD button.Once Auto Power Off has been disabled, the meter will no longer shut down automatically after 20 minutes. It will remain on until the button is pressed again to power off the instrument. Once the meter is powered off, Auto Power Off will automatically be re-enabled when the meter is powered on again. 14CALIBRATING THE METERThe DSM8925 must be calibrated beforeit can make accurate sound level measurements. To begin, obtain a standard acoustic calibrator with a 94 dB output, such as General Tools & Instruments’ SCAL1356. Then enter Manual Ranging mode and choose the 80 to 110 dB range using the steps outlined on p. 9. Changing the response time is unnecessary. However, make sure that “C”weighting is chosen and that that the meter is not operating in MAX HOLD mode.To calibrate the meter, insert its microphone in the hole of the acoustic calibrator. Power on the calibrator and set its output range to the range containing 94 dB. Using a small Philips-head screwdriver, turn the calibration adjustment screw on the right side of the DSM8925 until its display shows the same reading as the calibrator’s, ±0.1 dB.15SPECIFICATIONS Measurement Range40 to 130 dB overfour ranges Measurement Accuracy±2 dBDigital Display Resolution0.1 dBDigital Display Refresh160 milliseconds PeriodAnalog Bar Graph 1 dBResolutionAnalog Bar Graph 40 milliseconds Refresh PeriodFrequency Range31.5 Hz to 8 kHz Display Window Size 1.18 (W) x 1.38 (H) in.(30 x 35mm)Digit Height0.6 in. (15.2mm) Microphone 0.5 in. (12.7mm) Diameter/Type Electret condenser Battery Life60 hours (typical) Analog Output0 to 0.707Vrms Operating Temperature32° to 122°F(0° to 50°C)@<80% R.H. Storage Temperature-4° to 122°F(-20° to 50°C)@<90% R.H. Dimensions9 x 2.25 x 1.1 in.(230 x 57 x 28mm) Weight 4.6 oz. (130g) Power Source 4 “AAA” batteries16MAINTENANCE TIPSicon appears at the upper rightof the display, it’s time to replace the four AAA batteries that power the instrument (although measurements will remain valid for several hours after the icon first appears). To replace the batteries, follow the Setup Instructions on p. 8.Remove the batteries when storing the meter for an extended period of time.Do not drop or disassemble the meter or immerse it in water.WARRANTY INFORMATIONGeneral Tools & Instruments’ (General’s) DSM8925 Digital Sound Level Meter with Jumbo Display is warranted to the original purchaser to be free from defects in material and workmanship for a period of one year. Subject to certain restrictions, General will repair or replace this instrument if, after examination, the company determines it to be defective in material or workmanship. This warranty does not apply to damages that General determines to be from an attempted repair by non-authorized personnel or misuse, alterations, normal wear and tear, or accidental damage. The defective unit must be returned to General Tools & Instruments or to a General-authorized service center, freight prepaid and insured.17Acceptance of the exclusive repair and replacement remedies described herein is a condition of the contract for purchase of this product. In no event shall General be liable for any incidental, special, consequential or punitive damages, or for any cost, attorneys’fees, expenses, or losses alleged to be a consequence of damage due to failure of, or defect in any product including, but not limited to, any claims for loss of profits. RETURN FOR REPAIR POLICYEvery effort has been made to provide you with a reliable product of superior quality. However, in the event your instrument requires repair, please contact our Customer Service to obtain an RGA (Return Goods Authorization) number before forwarding the unit via prepaid freight to the attention of our Service Center at this address:General Tools & Instruments80 White StreetNew York, NY 10013212-431-6100Remember to include a copy of your proof of purchase, your return address, and your phone number and/or e-mail address.18NOTES________________________________ ________________________________ ________________________________ ________________________________ ________________________________ ________________________________ ________________________________ ________________________________ ________________________________ ________________________________ ________________________________ ________________________________ ________________________________ ________________________________ ________________________________ ________________________________ ________________________________ ________________________________ ________________________________19GENERAL TOOLS & INSTRUMENTS80 White StreetNew York, NY 10013-3567PHONE (212) 431-6100FAX (212) 431-6499TOLL FREE (800) 697-8665e-mail:**********************DSM8925 User’s Manual Specifications subject to change without notice ©2011 GENERAL TOOLS & INSTRUMENTSNOTICE - WE ARE NOT RESPONSIBLE FOR TYPOGRAPHICAL ERRORS.MAN#DSM8925 6/20/11。

Agilent8920/8921通信测试仪(综测)使用说明一、仪器面板键盘操作及菜单1、面板CRT显示●RX TEST—接收机测试屏幕，可显示RF和AF控制及接收机测试结果。

●TX TEST—发射机测试屏幕，可显示RF和AF控制及发射机测试结果。

●DUPLEX TEST—双工测试屏幕，可同时显示RF和AF控制及收发信机测试结果。

●TESTS—访问来自存储卡、内部ROM/RAM及外接磁盘驱动器装入的程序，可对其编辑与自动运行的屏幕，显示测试结果。

●RF GENERATOR—射频信号源屏幕，用于显示射频与调制信号的控制及测试结果。

●RF ANAL YZER—射频分析仪屏幕，用于显示射频与解调信号的控制及测试结果。

●AF ANAL YZER—音频分析仪屏幕，用于显示音频信号的控制与测试结果。

●OSCILLOSCOPE—示波器屏幕，用于完成对示波器的控制及显示测量结果。

●SPECTRUM ANAL YZER—频谱分析仪屏幕。

●SIGNALING ENCODER—信令编码器屏幕。

●SIGNALING DECODER—信令解码器屏幕。

●RADIO INT—无线电接口与屏幕，显示仪器内置无线电接口卡对外接模块与设备的自动测试结果。

2、面板连接器与控制器●POWER—仪器的电源开关键。

●RF IN/OUT连接器—是一阻抗为50Ω的N型阴性插座，用作射频信号源的输出与调制分析仪的输入接口，允许连续输入60W，或输入100W功率。

●DUPLEX OUT连接器—是一阻抗为50Ω的BNC型阴性插座，用作射频信号源及跟踪信号源的输出端口。

●ANT IN连接器—用作小功率射频信号（≤200Mw）及空中信号的输入端口。

●MIC/ACC接口—是一8针DIN接口，可提供多种用途的连接：MIC IN—当KEY IN接地时去调制射频发生器（先滤波与放大）；KEY IN—用于射频信号源的输出开/关状态控制，及在TX TEST与RX TEST屏幕之间的转换控制；KEY OUT1与KEY OUT2用于一部外设的开/关控制。

DS8922/DS8922A/DS8923A TRI-STATE ®RS-422Dual Differential Line Driver and Receiver PairsGeneral DescriptionThe DS8922/22A and DS8923A are Dual Differential Line Driver and Receiver pairs.These devices are designed spe-cifically for applications meeting the ST506,ST412and ESDI Disk Drive Standards.In addition,the devices meet the requirements of the EIA Standard RS-422.These devices offer an input sensitivity of 200mV over a ±7V common mode operating range.Hysteresis is incorpo-rated (typically 70mV)to improve noise margin for slowly changing input waveforms.An input fail-safe circuit is pro-vided such that if the receiver inputs are open the output assumes the logical one state.The DS8922A and DS8923A drivers are designed to provide unipolar differential drive to twisted pair or parallel wire trans-mission plementary outputs are logically ANDed and provide an output skew of 0.5ns (typ.)with propagation delays of 12ns.Both devices feature TRI-STATE outputs.The DS8922/22A have independent control functions common to a driver and receiver pair.The DS8923A has separate driver and receiver control functions.Power up/down circuitry is featured which will TRI-STATE the outputs and prevent erroneous glitches on the transmis-sion lines during system power up or power down operation.The DS8922/22A and DS8923A are designed to be compat-ible with TTL and CMOS.Featuresn 12ns typical propagation delay n Output skew —±0.5ns typicaln Meets the requirements of EIA Standard RS-422n Complementary Driver Outputsn High differential or common-mode input voltage ranges of ±7Vn ±0.2V receiver sensitivity over the input voltage range n Receiver input fail-safe circuitryn Receiver input hysteresis —70mV typical n Glitch free power up/down nTRI-STATE outputsConnection DiagramsDS8922A Dual-In-Line00851101Order Number DS8922M,DS8922N,DS8922AM or DS8922ANSee NS Package Number M16A or N16ETRI-STATE ®is a registered trademark of National Semiconductor Corp.July 2004DS8922/DS8922A/DS8923A TRI-STATE RS-422Dual Differential Line Driver and Receiver Pairs©2004National Semiconductor Corporation Connection Diagrams(Continued)DS8923A Dual-In-Line00851102Order Number DS8923AM,DS8923AN,See NS Package Number M16A or N16EDS8922/22AEN1EN2RO1RO2DO1DO200ACTIVE ACTIVE ACTIVE ACTIVE 10HI-Z ACTIVE HI-Z ACTIVE 01ACTIVE HI-Z ACTIVE HI-Z 11HI-ZHI-Z HI-ZHI-ZDS8923ADEN REN RO1RO2DO1DO200ACTIVE ACTIVE ACTIVE ACTIVE 10ACTIVE ACTIVE HI-Z HI-Z 01HI-Z HI-Z ACTIVE ACTIVE 11HI-ZHI-ZHI-ZHI-ZD S 8922/D S 8922A /D S 8923A 2Absolute Maximum Ratings(Note1)If Military/Aerospace specified devices are required, please contact the National Semiconductor Sales Office/ Distributors for availability and specifications.Supply Voltage7V Drive Input Voltage−0.5V to+7V Output Voltage 5.5V Receiver Output Sink Current50mA Receiver Input Voltage±10V Differential Input Voltage±12V Maximum Package Power Dissipation@+25˚CM Package1300mW N Package1450mWDerate M Package10.4mW/˚C above+25˚CDerate N Package11.6mW/˚C above+25˚CStorage Temperature Range−65˚C to+165˚C Lead Temp.(Soldering,4seconds)260˚C ESD Rating(HBM)2000V+Recommended Operating ConditionsMin Max Units Supply Voltage 4.5 5.5V Temperature(T A)070˚CDS8922/22A and DS8923A Electrical Characteristics(Notes2,3,4)Symbol Conditions Min Typ Max Units RECEIVERV TH−7V≤V CM≤+7V−200±35+200mVV HYST−7V≤V CM≤+7V1570mVR IN V IN=−7V,+7V(Other Input=GND) 4.0 6.0kΩI IN V IN=10V 3.25mAV IN=−10V−3.25mAV OH V CC=MIN,I OH=−400µA 2.5VV OL V CC=MAX,I OL=8mA0.5VI SC V CC=MAX,V OUT=0V−15−100mADRIVERV OH V CC=MIN,I OH=−20mA 2.5VV OL V CC=MIN,I OL=+20mA0.5VI OFF V CC=0V,V OUT=5.5V100µA|VT|–|VT|0.4VVT 2.0V|V OS–V OS|0.4VI SC V CC=MAX,V OUT=0V−30−150mADRIVER and RECEIVERI OZ V OUT=2.5V50µATRI-STATE V CC=MAX V OUT=0.4V−50µALeakageI CC V CC=MAX ACTIVE76mATRI-STATE78mADRIVER and ENABLE INPUTSV IH 2.0VV IL0.8VI IL V CC=MAX,V IN=0.4V−40−200µAI IH V CC=MAX,V IN=2.7V20µAI I V CC=MAX,V IN=7.0V100µAV CL V CC=MIN,I IN=−18mA−1.5VDS8922/DS8922A/DS8923A3Receiver Switching Characteristics(Figures 1,2,3)ParameterConditions MinTypMaxUnits89228922A/23AT pLH CL =30pF 1222.520ns T pHLCL =30pF 1222.520ns |T pLH –T pHL |CL =30pF 0.55 3.5ns Skew (Channel to Channel)CL =30pF0.5 3.02.0ns T pLZ CL =15pF S2Open 15ns T pHZ CL =15pF S1Open 15ns T pZL CL =30pF S2Open 20ns T pZHCL =30pF S1Open20ns Driver Switching CharacteristicsParameterConditionsMinTypMaxUnits89228922A/23ASINGLE ENDED CHARACTERISTICS (Figures 4,5,6,8)T pLH CL =30pF 121515ns T pHL CL =30pF 121515ns T TLH CL =30pF 51010ns T THLCL =30pF 51010ns |T pLH –T pHL |CL =30pF 0.5ns SkewCL =30pF (Note 5)0.55 3.5ns Skew (Channel to Channel)0.5 3.02.0ns T pLZ CL =30pF 15ns T pHZ CL =30pF 15ns T pZL CL =30pF 20ns T pZH CL =30pF 20ns DIFFERENTIAL SWITCHING CHARACTERISTICS (Note 6),(Figure 4)T pLH CL =30pF 121515ns T pHLCL =30pF 121515ns |T pLH –T pHL |CL =30pF 0.56.02.75nsNote 1:“Absolute Maximum Ratings”are those values beyond which the safety of the device cannot be guaranteed.They are not meant to imply that the device should be operated at these limits.The Table of “Electrical Characteristics”provides conditions for actual device operation.Note 2:All currents into device pins are shown as positive values;all currents out of the device are shown as negative;all voltages are referenced to ground unless otherwise specified.All values shown as max or min are classified on absolute value basis.Note 3:All typical values are V CC =5V,T A =25˚C.Note 4:Only one output at a time should be shorted.Note 5:Difference between complementary outputs at the 50%point.Note 6:Differential Delays are defined as calculated results from single ended rise and fall time measurements.This approach in establishing AC performance specifications has been taken due to limitations of available Automatic Test Equipment (ATE).The calculated ATE results assume a linear transition between measurement points and are a result of the following equations:Where:Tcp =Crossing PointTra,Trb,Tfa and Tfb are time measurements with respect to the input.D S 8922/D S 8922A /D S 8923A 4Switching Time Waveforms00851103AC Test Circuits and Switching Waveforms00851104FIGURE 1.00851105FIGURE 2.DS8922/DS8922A/DS8923A5AC Test Circuits and Switching Waveforms(Continued)00851106S1S2S3T PLZ Closed Open +2.5V T PHZ Open Closed −2.5V T PZL Closed Open +2.5V T PZHOpenClosed−2.5VFIGURE 3.00851107FIGURE 4.00851108FIGURE 5.D S 8922/D S 8922A /D S 8923A 6AC Test Circuits and Switching Waveforms(Continued)00851109FIGURE 6.00851110FIGURE 7.00851113FIGURE 8.DS8922/DS8922A/DS8923A7Typical Performance Characteristics(DS8923A)Driver V OH vs I OH vs TemperatureDriver V OH vs I OH vs V CC0085111400851115Driver V OL vs I OL vs TemperatureDriver V OL vs I OL vs V CC0085111600851117Receiver V OH vs I OHvs TemperatureReceiver V OH vs I OH vs V CC0085111800851119D S 8922/D S 8922A /D S 8923A 8Typical Performance Characteristics(DS8923A)(Continued)Receiver V OL vs I OLvs Temperature Receiver V OL vs I OL vs V CC0085112000851121Driver Differential Propagation Delay vs Temperature Driver Differential PropagationDelay vs V CC0085112200851123Receiver Propagation Delay vs TemperatureReceiver PropagationDelay vs V CC0085112400851125DS8922/DS8922A/DS8923A 9Typical Performance Characteristics(DS8923A)(Continued)Driver V OD vs TemperatureDriver V OD vs V CC0085112600851127Driver V OD vs R LDriver Differential TransitionTime vs Temperature0085112800851129Driver Differential TransitionTime vs V CCSupply Current vs Temperature0085113000851131D S 8922/D S 8922A /D S 8923A 10Typical Performance Characteristics(DS8923A)(Continued)Supply Current vs V CC I CC vs Driver Switching Frequency0085113200851133Driver Short Circuit Current vs Temperature Driver Short Circuit Current vs V CC0085113400851135Receiver Short Circuit Current vs TemperatureReceiver Short CircuitCurrent vs V CC0085113600851137DS8922/DS8922A/DS8923A 11Typical ApplicationsESDI Application00851111ST504and ST412Applications00851112D S 8922/D S 8922A /D S 8923A 12Physical Dimensionsinches (millimeters)unless otherwise notedSO Package (M)Order Number DS8922M,DS8922AM,or DS8923AMNS Package Number M16AMolded Dual-In-Line Package (N)Order Number DS8922N,DS8922AN,or DS8923ANNS Package Number N16EDS8922/DS8922A/DS8923A13NotesLIFE SUPPORT POLICYNATIONAL’S PRODUCTS ARE NOT AUTHORIZED FOR USE AS CRITICAL COMPONENTS IN LIFE SUPPORT DEVICES OR SYSTEMS WITHOUT THE EXPRESS WRITTEN APPROVAL OF THE PRESIDENT AND GENERAL COUNSEL OF NATIONAL SEMICONDUCTOR CORPORATION.As used herein:1.Life support devices or systems are devices or systems which,(a)are intended for surgical implant into the body,or (b)support or sustain life,and whose failure to perform when properly used in accordance with instructions for use provided in the labeling,can be reasonably expected to result in a significant injury to the user. 2.A critical component is any component of a life support device or system whose failure to perform can be reasonably expected to cause the failure of the life support device or system,or to affect its safety or effectiveness.BANNED SUBSTANCE COMPLIANCENational Semiconductor certifies that the products and packing materials meet the provisions of the Customer Products Stewardship Specification (CSP-9-111C2)and the Banned Substances and Materials of Interest Specification (CSP-9-111S2)and contain no ‘‘Banned Substances’’as defined in CSP-9-111S2.National Semiconductor Americas Customer Support CenterEmail:new.feedback@ Tel:1-800-272-9959National SemiconductorEurope Customer Support CenterFax:+49(0)180-5308586Email:europe.support@Deutsch Tel:+49(0)6995086208English Tel:+44(0)8702402171Français Tel:+33(0)141918790National Semiconductor Asia Pacific Customer Support CenterEmail:ap.support@National SemiconductorJapan Customer Support Center Fax:81-3-5639-7507Email:jpn.feedback@ Tel:81-3-5639-7560D S 8922/D S 8922A /D S 8923A T R I -S T A TE R S -422D u a l D i f f e r e n t i a l L i n e D r i v e r a n d R e c e i v e r P a i r sNational does not assume any responsibility for use of any circuitry described,no circuit patent licenses are implied and National reserves the right at any time without notice to change said circuitry and specifications.。