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信号完整性研发测试攻略——Ver1.0编写：黄如俭（samHuang）钱媛（TracyQian）宋明全（IvanSong）目录1.CLKTest.......................................................................................................................................31.1DifferentialSignalTest....................................................................................................31.2SingleSignalTest............................................................................................................52.LPCTest........................................................................................................................................72.1ECSideTest.....................................................................................................................72.2ControlSidseTest.........................................................................................................83.USBTest.....................................................................................................................................113.1HighSpeedTest.............................................................................................................113.2LowSpeedTest..............................................................................................................123.3FullSpeedTest...............................................................................................................123.4Drop/DroopTest.............................................................................................................124.VGATest.....................................................................................................................................144.1R、G、BSignalTest....................................................................................................144.2RGBChanneltoChannelSkewTest.............................................................................144.3VSYNCandHSYNCTest.............................................................................................154.4DDC_DATAandDDC_CKLTest..................................................................................155.LVDSTest...................................................................................................................................175.1DifferentialdatasignalsswingTest..............................................................................175.2CheckingSkewatreceiverTest.....................................................................................185.3CheckingtheoffsetvoltageTest....................................................................................195.4DifferentialInputVoltageTest......................................................................................205.5CommonModeVoltageTest.........................................................................................205.6SlewRateTest...............................................................................................................215.7DatatoClockTimingTest.............................................................................................236.FSBTest......................................................................................................................................267.DMI/FDITest..............................................................................................................................298.HDAudioTest............................................................................................................................308.1MeasurementatTheController......................................................................................308.2MeasurementatTheCodec.........................................................................................311.CLKTest1.1DifferentialSignalTest测试设备：示波器，两个差分探头，鼠标，键盘测试软件：3DMARK，负载测试步骤：（1）开启示波器预热30分钟，运行测试软件。连接差分探头，鼠标，和键盘。对示波器的probes和channals进行calibration和deskew。（2）参照测试平台的芯片datasheet,使用AllegroSPB软件，在电路板上找出被测信号测试点,记录下过孔或芯片管脚的位置。找出待测信号接收端的参数标准。如图1.1图1.1（3）连接电路板的附属小板，显示屏，电源，将示波器和电路板共地。开启电路板，正常进入系统，运行3DMark。（4）参照被测信号测试标准，在示波器（Agilent）的菜单选项中选择对应的测试项Frequency/Period/DutyCycle/HighTime/LowTime/cyc-cyc-jitter.Spec中有约束条件的要进行条件设置。如图1.2图1.2（5）用一个差分探头连接差分信号测试点，调节示波器，抓取所需要的波形，并保存。（6）清除之前的测试选项和波形。再次从菜单选项中选择测试项。Risetime/Falltime/Overshoot/Undershoot/Highlevel/Lowlevel（7）根据测试标准的要求，选择相应的探头。如果要求使用单端探头，将探头的“+”端接信号测试点，“-”端接地；如果要求使用差分探头，将探头连接差分信号的两个测试点，调节示波器，抓取所需要的波形，并保存。（8）Vcross的测试：a.用两个单端探头的“+”极分别连接clk信号的P/N极，“—”极连接差分信号测试点最近的地。在同一屏幕上显示两个通道的波形，调整参数使两个通道的OFFSET，单位幅值相同，抓取密集波形。调出marker,用两条横向的坐标分别卡出两条信号线交点（同一信号相同的边沿）的最大值和最小值。如图1.3图1.3b.使用无限累积功能，抓取一个交点的累积波形。调出Marker,用两条横向坐标轴分别卡出交点的最大值和最小值。两条横项坐标轴的值就是V_cross的值。如图1.4图1.4（9）Vcrossdetal的测试：依照Vcross的测试方法，测出Vcross的最大值和最小值，两值的差（即两条Marker值差的绝对值）就是Vcrossdetal.测试标准：将测得的数据与测试标准对照，判断测试结果是否在标准之内。若在，则测试结果合格，定为PASS。若不在标准之内，则测试结果不合格，定为FAIL。注意事项：(1)测试时，要将示波器与电路板共地。(2)测试Risetime/Falltime/Overshoot/Undershoot/Highlevel/Lowlevel时，依据给定的标准选择使用差分探头或时单端探头。(3)对于测试标准中有约束条件的测试项，要按照标准更改示波器的条件设置，测得的数据才可与标准值比对。比如，对高电平和低电平范围的规定。(4)信号的测试标准参考接收芯片端data