DFE Tutorial

PollEx DFE is one of many PollEx toolsets and it checks electrical validity of PCB design. PollEx DFE can be launched within PollEx PCB and it helps designers to reduce design errors that may be detected later in electrical test processes. The PollEx DFE results can be outputted to a well-formatted MS/Excel spreadsheet. With a vast variety of user-friendly electrical rule checking options, PollEx DFE helps you to reduce cost and time to produce good working PCBs fast.

This tutorial is primarily designed to enable you to get a quick start with the PollEx DFE tool. It is not intended to be a complete reference guide for all the available test items but will give you an overview of key concepts. Understanding these concepts will allow you to learn how to use this tool efficiently with the help of the online documentation. Access the help by pressing the F1 key.

This tutorial shows simple design verification flow using PollEx DFE with fairly simple design. Studying this example carefully will help you become familiar with the PollEx DFE tool.

In this section, you will check if high speed signals cross over split plane, and check DDR bus robustness.

After downloading the file, uncompress the file and save it into a folder. That file saving folder is the job folder in this tutorial.

Open and Preview PCB Design

In this step, you will open a design file in PollEx PCB and preview PCB design.

  1. From the menu bar, click File > Open and open the DFE_Sample.pdbb file from C:\Temp\Altair-PollEx\PollExDFE.
  2. Preview the PCB design.
  3. From the menu bar, click Option > DFE > Input to open PollEx DFE.
    The PollEx DFE Input dialog displays.

Check Copper Cross Over Detect

  1. Activate the Copper Cross Over Detect checkbox.
    The Copper Cross Over Detect dialog displays.

    To check if high speed signal cross over split plane, you will define power/ground net group and define target net group, high-speed net group.

  2. Click the classification menu.
    The PollEx DFE Input dialog displays.
  3. Define GND_Plane net group.
    1. In the Net Group Type section, double-click Net Group01 and change the group name to GND_Plane by double-clicking the Name column.
    2. Select Select Nets From List from the context menu.


      Figure 1.
      The Select Nets from List dialog displays.
    3. Select the following multiple nets from the net list: GND, GND_ADC, GND_LV, GND_OSC, GND_PLL, and GNDADC.
      Those signals are plane type ground signals that can be a reference plane.
    4. Click Add to List to add selected net lists to selected items.
    5. Click Done.
      The selected list registers as a net group with the name GND_Plane.


      Figure 2.
  4. Define PWR_Plane net group.
    1. In the Net Group Type section, double-click Net Group02 and change the group name to PWR_Plane by double-clicking the Name column.
    2. Select the Select Nets From List from the context menu.
      The Select Nets from List dialog opens.


      Figure 3.
    3. Select the following multiple nets from the net list: VCC3P3_SYS, VCC_1P5_DDR, VCC1P5_SYS, VCC1P0_CORE, VCC1P0_USB, and VCC1P2_HSIC.
      Those signals are plane type power signals that can be a reference plane.
    4. Click Add to List to add selected net lists to the selected item.
    5. Click Done.
      The selected list registers as a net class with the name, PWR_Plane.


      Figure 4.
  5. Define High-Speed net group.
    1. In the Net Group Type section, double-click Net Group03 and change the group name to High_Speed by double-clicking the Name column.
    2. Select Selected Nets From List from the context menu.
      The Select Nets from List dialog opens.


      Figure 5.
    3. Select high speed nets from the signal net list.
      The following nets are considered as high-speed signal.
      • MCU_SCL_0
      • MCU_ACKP
      • MCU_ACKN
      • MCU_DQS0P
      • MCU_DQS0N
    4. Click Add to List to add the selected net list to the selected item.
    5. Click Done.
      The selected list registers as a net class with the name, High_Speed. There are now three required net groups: GND_Plane, PWR_Plane, and High-Speed.
  6. Activate the Copper Cross Over Detect checkbox to set test condition.
    The Copper Cross Over Detect Item Rule Entry dialog opens.
  7. Set Copper Cross Over Detect test condition.
    1. Double-click the Net Group field.
      The Select Net Group dialog should be visible.
    2. Select High-Speed net group, then click OK.
    3. Double-click the Plane Net field.
      The Select Net Group dialog should be visible.
    4. Select GND_Plane and PWR_Plane net groups and click OK.
    5. Select L1 Layer in the Check Layer section to check one layer above and below.
    6. Activate Include Pass Data.
      The passed items are also reported in addition to the failed items.


      Figure 6.
      With this setting, PollEx DFE will check if MCU_SCL_0, MCU_DQS0P/N, MCU_ACKP/N signals cross over ground plane or power plane split. The passed items are also reported in addition to the failed items.
  8. Run Copper Cross Over Detect Item and review Check Result.
    1. Click Save As and save this input file as training.DFESI in the PollExDFE folder under job folder.
      Note: Click Load to reload this input setup condition.
    2. Click Start Checking.
      PollEx DFE starts checking for selected checking items. After running, PollEx DFE changes its window for results display.
    3. In the result tab, select Copper Cross over Detect and choose the first error checking item.


      Figure 7.
      In the right window, an enlarged image of the error area is displayed. The cyan colored circle is the point where the error occurred.
    4. In the result tab, choose the second error checking item.
      MCU_SCL_0 signal cross over GND plane split area at Layer2.


      Figure 8.

      The second error case is that net cross-over plane split area, and first error case is that net cross-over anti-pad area of itself.

      You can ignore first error case by using the PIN/VIA Escape option.

    5. In the result tab, click View Input.
    6. Activate Copper Cross Over Detect in the Check Item Category section to set test condition.
      The Copper Cross Over Detect dialog displays again.
    7. Activate PIN/VIA Escape and assign value 0.5 to exclude pin and via anti-pad area of target signal itself.
      With this input condition, if target nets cross over the anti-pad of target signal smaller than 0.5mm will be ignored.
    8. Click Start Checking.
    9. Click Save.
      PollEx DFE starts checking with new input condition. After running, PollEx DFE changes its window for results to display.
    10. In the result tab, select Copper Cross over Detect and choose the first error checking item.
      The first case error is removed.
    11. Select other checked items and review the results the same way.

Create Excel Report

In this step, you will create an Excel report for the result.

PollEx DFE has a feature to make a report for checking results into a file.
  1. Click Excel Export and select User Defined Excel Format.


    Figure 9.
    The User Defined Export Excel dialog displays.

    You can use company standard excel report format. In that case, save the excel format file into any location you want. The blank excel format file is located in the C:\ProgramData\altair\PollEx\<version_number>\Data\Excel-Report directory. (DFE_BaseExcel.xls)

  2. Page1 settings.
    1. Set Excel File Path.
      You can select your own format by clicking . You will use the default excel format.
    2. Select Net Summary Sheet Name for net summary reporting.
    3. Select Automatically record all available Contents to MS/Excel.
    4. Enter 39 for Result Data Column No., and click Apply to extend the column count to 39.
    5. Select User Header Name On Excel File.
      In the User Defined Export Excel dialog, your settings should now look as follows:


      Figure 10.
    6. Click Next.
  3. Page2 Setting.
    The next step is to set excel row format. The upper section shows the total available result items. The lower section shows the selected item for excel report. You can choose the required item from the upper section window list, and click ADD to move the selected item into the lower section window. Since you already selected Automatically record all available Contents to MS/Excel, other settings can be left unchanged.


    Figure 11.
    1. Click Next.
  4. Page3 settings.
    The next step is to set the excel column format. You can set the contents to be saved in the columns of the Excel report.
    1. Select Predefined Item to set the column with PollEx pre-defined items, and click Set Predefined Item List.
    2. Select all items named BLANK, and remove them by clicking Remove All.
    3. Select all items available in the left section of the dialog, except the first item named [BLANK], and click Add.
    4. Activate Apply Set Same Value in the Column.
      Your settings should now look as follows:


      Figure 12.
    5. Click OK to close the Predefined Item dialog.
      The User Defined Export Excel dialog should now look as follows:


      Figure 13.
    6. Click Save As and save the report setup environment file as training.DFEE in the PollExDFE folder under job folder.
      You can reload this report setup condition by clicking Load.
    7. Click Finish/Export Excel to start the excel report creation.
      PollEx DFE starts generating the excel report. The PollEx DFE shows the excel report file.
    8. Save the excel file with a different name.
      It is better to keep the sample excel format file for future use.

Check Bus2

  1. Click View Input to open the Input Setting dialog.
    The PollEx DFE Input dialog displays.
  2. Activate Bus2 in the Check Item Category list.
    The Bus2 Item Rule Entry dialog displays.
  3. Define Component groups.
    To set component groups, you will use the PollEx DFE Input dialog.
    1. In the dialog, click the classification menu above the Check Item Category section.


      Figure 14.
      The PollEx DFE Input dialog opens.
  4. Define CPU component group.
    1. In the Component Group Type section, click the first item, Component Group01, and change the group name to CPU.
    2. Select Selected Component from List from the context menu.


      Figure 15.
      The Selected Component from List dialog opens.
    3. Select the IC-NXP4330 component from the part name list.
    4. Click Add to add selected components to the selected item.
    5. Press OK to close this dialog.
      The selected list registers as a component group with the name CPU.
  5. Define Memory component group.
    1. In the Component Group Type section, click the second item, Component Group02, and change the group name to Memory.
    2. Select Selected Component from List from the context menu.
      This menu shows you the part list.
    3. Select the component H5TQ4G63AFR from the part name list.
    4. Click Add to add the selected component to the selected item.
    5. Click OK to close this dialog.
      The selected list registers as a component group with the name Memory.
  6. Define DDR_Data0 net group.
    1. In the Net Group Type section, click the fourth item, Net Group04, and change the group name to DDR_Data0.
    2. Select Select Nets From List from the context menu.
      This menu shows you the net list.
    3. Select multiple nets MCU_D0~D7 and MCU_DQM0 from the signal net list.
      These signals are considered as data byte0 of DDR data bus.
    4. Click Add to List to add the selected nets to the selected item.
    5. Click Done.
      The selected list registers as a net group with the name DDR_Data0.
  7. Define DDR_Strobes net group.
    1. In the Net Group Type section, click the fifth item, Net Group05, and change the group name to DDR_Strobes.
    2. Select Select Nets from List from the context menu.
      This menu shows you the net list.
    3. Select the following multiple nets from the signal net list:
      • MCU_DQS0P, MCU_DQS0N
      • MCU_DQS1P, MCU_DQS1N
      • MCU_DQS2P, MCU_DQS2N
      • MCU_DQS3P, MCU_DQS3N
      These signals are strobe signals for DDR data byte0~3 bus.
    4. Click Add to List to add the selected nets to the selected item.
    5. Click Done to close this dialog.
      The selected list registers as a net group with the name DDR_Strobes.
  8. Activate Bus2 in the Check Item Category list.
    The Bus2 item rule entry dialog displays.
  9. Set Bus2 test condition.
    1. Double-click the Net field in the Bus2 input setup dialog to select the target net from the net group list.
      The Select Object Group dialog displays.
    2. Select DDR_Data0 as the target net group, then click OK to close this dialog.
    3. Double-click the Base Net field in the Bus2 input setup dialog to select strobe net from the net group list.
      The Select Object Group dialog displays.
    4. Select the DDR_Strobes net group as a strobe net group and click OK.
    5. Activate the Filter option.
    6. Double-click the Filter field in the Bus2 input setup dialog to select MCU_DQS0P and MCU_DQS0P among the nets included in the DRAM_Strobes net group list.
      The Netlist Filter dialog displays.


      Figure 16.
    7. Enter the Base Net name filter as 0P and enter the Pair Net name filter 0N.
    8. Click Add Filter.


      Figure 17.
    9. Click OK.
    10. Double-click the Start Component field in the Bus2 input setup dialog to select Start Component from the component group list.
      The Select Object Group dialog opens.
    11. Select CPU as a start component group and click OK.
  10. The Net Length Check condition setup.
    1. Double-click the Net Length Check field in the Bus2 input setup dialog to set the Net Length Check test condition.
      The Net Length Check dialog opens.
    2. Activate the Tolerance checkbox.
    3. Activate the Value checkbox.
    4. Enter the Min Range value 0.254.
    5. Enter the Max Range value 0.254.
    6. Activate the Max Length checkbox and enter 11 for the value.
    7. Activate the Check Width Difference checkbox, and enter 10 for Tolerance.
      In the Net Length Check dialog, your settings should now look as follows:


      Figure 18.
    8. Click OK.
  11. The Routing Check condition setup.
    1. Double-click the Routing Check field in the Bus2 input setup dialog to set the Routing Check test condition.
      The Routing Check setup dialog opens.
    2. Activate the Inner Routing Ratio checkbox.
    3. Activate the Ratio checkbox.
    4. Enter 80 for the Min Value.
    5. Activate the Routing Symmetry checkbox.
    6. Activate the Ratio checkbox.
    7. Enter 10 for the Max Difference value.
      In the Routing Check dialog, your settings should now look as follows:


      Figure 19.
    8. Click OK.
  12. The Via Check condition setup.
    1. Double-click the Via Check field in the Bus2 input setup dialog to set the Via Check test condition.
      The Via Check dialog opens.
    2. Activate the Via Check checkbox.
    3. Activate the Max checkbox.
    4. Enter 3 for the Qty value.
    5. Activate the Via Symmetry checkbox.
      In the Via Check dialog, your settings should now look as follows:


      Figure 20.
    6. Click OK.
    With this setting, PollEx DFE checks the following:
    • If the length of DDR Data byte0 nets is between DQS net length – 0.254mm and DQS net length + 0.254mm.
    • If the length of DDR Data byte0 nets is longer than 11mm.
    • If the width of DDR data byte0 nets is the same as DQS nets within 10 percent range.
    • If the DDR data byte0 nets are routed on inner layer over 80 percent range.
    • If the inner routing ratio of DDR data byte0 nets is the same as the inner routing ratio of DQS nets within 10 percent range.
    • If the via count of DDR data byte0 and DQS nets is greater than three.
    • If the via count of each DDR data byte0 nets and DQS nets is the same.
  13. Run Bus2 Item and review Check Result.
    1. Unselect the Copper Cross over Detect test items in the Check Item Category section.
    2. Click Start Checking.
      PollEx DFE will ask you to save the current input file status or not.
    3. Click Save to save the current setup.
      PollEx DFE starts checking for the selected checking items. After running, PollEx DFE changes its window for results display.
    4. In the result tab, click [Net]Bus2 to see the detailed result.


      Figure 21.
  14. Review Net Length Check Result.
    1. Click Length to review the length check result.
    2. Choose the first error checking item of this section.
      You can see the error occurring location and its picture. You can also see that the trace length of MCU_DQS0N net is 19.721mm. It is longer than the limit 11mm, so it fails.


      Figure 22.
    3. Click Routing to review the routing check result.
    4. Choose the first error checking item of this section.
      The total routing length of MCU_DQS0N net is 19.7211mm. The required inner routing ratio is 80 percent. To meet the required inner routing ratio of 80 percent the inner routing length of the MCU_DQS0N net should be longer than 15.7769mm. The inner routing length of MCU_DQS0N is 15.1205mm, so it fails.
    5. Select other checked items and review the results the same way.