Mexico 3070 user group meeting 2012 test coverage john


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Mexico 3070 user group meeting 2012 test coverage john

  1. 1. 3070 User Group IMPROVING TEST Meeting 2012 COVERAGE Agilent Measurement System Division John Pendlebury Applications Engineer September 14, 20121
  2. 2. Agenda 1. Boundary Scan Test (3070 has full compliant, BSDL, Tricks and Treats) 2. CET for no access (example video memory device) 3. Device programming (u Processors, Automotive board devices, Serial prom, nand flash) 4. ISP inside the Control XTP Card 5. DLLs2
  3. 3. Features of our i3070 over the decade Throughput Coverage Ease of Use LED Test 2012 Rel 8.30P Windows 7  Ext DLL 60V Zener 2011 Rel 8.20P N5747A Pwr Supp Unit i3070 S5 DC test for big Caps 100KHz & 200KHz for small Caps 2010 Rel 8.10P RP5700 PC CET on IC Utility card TestPlan Analyzer 2009 Rel 8.00P ASRU N "AS"  Pwr Monitor Flexible Pwr Channels  High Pwr Channels Fixture Pwr Supp 2008 Rel 7.20P VTEP v2.0 CET VTEP enhanced guarding i3070 2008 Rel 7.10P VTEP speed up 1149.6  Enhanced Log record IPG enhanced Switch btw Mux : Unmux 2007 Rel 7.00P  VTEP v2.0 NPM Auto Optimizer Browser Pin locator New GUI  FPY, Worst Probe 2006 Rel 6.00P  XW4200 PC AutoDebug WinXP 2005 Rel 5.40P  iYET  iVTEP i3070 S3 Coverage Analyst NAND/XOR Tree Pattern User Fixture Component 2003 Rel 5.30P VTEP Scanworks GUI Localization ISP suite Auto Si nails 2001 Rel 4.00P-5.20P 50% faster in sys diag ControlXTP - SW5.0  Windows NT Panel Test < 2001 < Rel 4.00 Testjet Throughput Multiplier i3070 Software Updates3 9/14/2012
  4. 4. Diagnostic Capability for Coverage Definition Problem: If the ddr memory doesn‟t work… A: 70% memory read/write test. B: 100% boundary scan test. (if memory supports) C: 90% VTEP test. Which test method identifies the defects below? -Memory module failure  A -DIMM connector failure  C -Trace failure between CPU and memory.  A,B,C -CPU memory unit failure.  maybe A 100% always works ?? Must understand Diagnose- ability behind Coverage Definition
  5. 5. Defining test coverage varies from test Engineer to testengineer. Lets start with some basic degrees of test coverage:1. No test coverage2. Presence3. Presence and orientation4. Right part and orientated correctly5. Right part and some of the pins are tested6. Right part and all of the pins tested but not all of the part functions have been tested7. All of the part‟s functions have been tested8. Part has been functionally tested9. Part has been tested at speedPage 55 March 3, 2010
  6. 6. Common Defects in Process TestComponent on the PCB +- -+Presence Correctness Orientation Live Alignment Not presence Wrong correct device If polarized, Dead, Not working Not centered, it‟s revised or (not a full functional With skews or rotated qualification) small rotationsSolder Connection point of device to PCB These consist of the most comprehensive process test coverage formulaShort Open Quality PCOLA-SOQunwanted continuity lack of continuity malformation, excess orto other nearby between the board inadequate solder, coldconnection points and device solder voids, etc From Ken Parker “A New Process for Measuring and Displaying connection Board Test Coverage”.2002
  7. 7. Some of the tools that the 3070 has to increase test coverage• Automatic generation of test for unpowered analog.• VTEP and IVTEP to include Drive Through• Digital and Powered Analog test developed through test models• Boundary-Scan (simple and advanced)• Coverage Extend (combination of VTEP and Boundary-Scan)• Silicon Nails (combination of digital test and Boundary-Scan).• Agilent Bead Probe• NPM• Polarity Check• Ability to program devices (EEPROM, Flash, ISP) with both static and dynamic data.• The ability to allow the test engineer to write tests to cover unique situations (analog cluster, digital cluster, digital drive through)• Coverage Analyst Report• Test Access Consultant Measurement Systems DivisionPage 77 January 24, 2007
  8. 8. What is Boundary Scan ? To Test the Connectivity of each IC pin An International Standard Defined by IEEE, As IEEE 1149.1 from 1990In_ Out  Do not need to understand the1 _1 Core Device Function (Core Logic)In_ Out  Tester applies Data on inputs. Cells2 _2 capture data on inputs. DataTDI TDO scanned out TDO for verification.  Scan data in TDI to Output cells. Tester verifies data on outputs.  Save test access when in Bscan chain.8
  9. 9. Why IEEE 1149.1 ? What is the challenge ? IEEE, approved 1149.1 What is the solution? In 1990 ? We Talk About IEEE 1149.1What is IEEE1149.1? In 2012 Where is IEEE1149.1 used ?9
  10. 10. The Industry Challenges for Process Test* *Intel Testing Forum 2008 at Taipei :Challenges: Smaller Size, HDI, High Speed Signal Trace Results: * No Space for Test Access Traditional Test Pad create distortion in high speed signal *: Picture from Intel Testing Forum 2008 Taipei *10
  11. 11. Boundary Scan History in IEEE SOC IC Memory IC IC/PCB In-System Module/Sys Functioning Functioning connectivity Programmin Interacting 1990 ....................... ..IEEE 1149.1 g approved (single- 1991 ...... end digital) 1992 1993 . . . . . . . . . . . . . . . . . . . . . . . . . IEEE 1149.1 add BSDL 1994 .. .. .. .. .. .. . . . . . . . . . . . . . . . . . . . IEEE 1149.1 IEEE 1149.5 1995 . . . . . . . . . . . . . . . . . . . . . . . . . Revised. . . . . . . . . . . . . . . . . . . ..... .... approved 1996 1996 ............ 1997 1998 IEEE 1149.4 1999 ...... .................. .approved . (analog signal) 2000 . .. .. .. .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .IEEE 1532-2000 approved IEEE 1149.1 2001 . . . . . . . . . . . . . . . . . . . . . . . . .Revised IEEE 1532-2002 2002 . .. .. .. .. .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .approved 2003 . . . . . . . . . . . . . . . . . . . . . . . IEEE 1149.6 ........... .. 2004 . .IEEE.1500 .. .. approved (AC- 2005 .. approved IEEE P1581 differential ) 2006 Discussing 2007 IEEE 1149.7 2008 Discussing11
  12. 12. Some NEW Proposal from iEEETest Standards Description Purpose/Target Device  Boundary-scan testing methods to  Digital device with boundary-scan enabled IO pins and enable digital IO stuck-at fault supports the JTAG test port of 4 pins that is accessible to detection for IC interconnect defects. probing.  Boundary-scan controlled mixed-signal  Additional test pins (2 additional) to support analog AC/DC testing interface measurements through enabled IO pins.  Boundary-scan extension to support  Enables boundary-scan testing of high-speed differential (DC testing of “Advanced” IO pins. or AC coupled) IO pins, especially SERDES pins.  In-system programming (ISP) through  Allows concurrent programming of large memories (typically boundary-scan interface non-volatile) within programmable logic devices.  Boundary-scan extensions to support  IO interfaces and power management features in today‟s IC‟s complex device initialization and post- require more sophisticated initialization sequences to prepare test pin quiescence. the device and PCAs for safe/reliable testing.  Boundary-scan extensions to support  Enable IO pins to selectively toggle digital state to enable AC- vector-less open fault measurements. coupled capacitive sensor (no direct electrical probe access) to measure solder open defects.  I/O Loopback testing for devices that  Enables boundary-scan IC‟s to validate interconnections to commonly do not have 1149.1. attached memory devices with loopback test.  Boundary-scan extensions to support  Enables description and much more efficient access to IC efficient access to user-defined BIST and Embedded Measurement capabilities increasingly registers and internal instrumentation. designed into complex IC‟s.
  13. 13. DFT for Boundary Scan TestRule #1 TCK Pull-Down, TMS Pull-UpRule #1.1: Pull-down R for TCK. Bscan Cells Connect TCK through 100 ohm resistor to Ground. For low voltage logic(<1.5volt), The Designer may use 50 ohm resistor. Core +Vcc Logic +VccRule #1.2: Pull-Up R for TMS. Connect TMS through 1.2Kohm pull up resistor to high.Note1: The TDI, TDO, are also suggested to have proper pull-up R TEST ACCESS R resistor to Vcc, So to have a stable input and output signal. The PORT Resistor could be 100 or 50ohm as TCK. Or other values, like several K ohms. TDI CONTROLLER (TAP) TDONote 2: If TRST# is used here, A high R ( like 1.2K or even higher ) to Vcc can be used here . Some ICs may use pull-down resistor. In that case, user needs to keep TRST# in high during bscan +Vcc testing. TCKNote3 : User may reference the IC Design Document to see the exact TMS resistor suggestion from the IC designer. Generally, the pull-Up resistor is recommended from many ICs. But some will require 100 or 50 a pull-down R instead. Be sure to reference the design-guide document.. 1.2K OhmNote4: User can consider to change the value of pull-up/down resistor Ohm TRST# here, The value of resistors may impact the overall power consumption. Lower value resistor requires stronger external driver capability. Pay attention here when changing test platform. 1.2K Test Ohm Access13
  14. 14. DFT for Boundary Scan TestRule #2 Chain Boundary Scan Devices in OrderRule #2.1: TDO connects to TDI in serial Connect 1st Boundary IC’s TDO to 2nd Boundary IC’s TDI , 2nd IC’s TDO to 3rd IC’s U1 TDI…etc. U3Rule #2.2: TCK , TMS connects in parallel U2 Connect all TCK and TMS in parallel. TDI TDO TDI TDO TDI TDO TCK TMS TCK TMS TCK TMSNote1: In some cases, when the board designer has more flexibilities in layout arrangement and if there is a new, unverified Boundary IC, We suggest to put this IC be end of the Bscan chain.Note2: For any IC, It‟s good to keep TDI away from TDO to avoid possible “short” between TDI/TDO. Board designer may consider to keep a proper distance under the overall space consideration.Note3: If more ICs in the chain, The TCK, TMS propagation may not #2.2 be effective as in lesser-IC-chain. In that Case, User may consider to put Buffer Circuitry for TCK/TMS, To get a better TCK/TMS synchronization. #2.1 TCK-TMS TDO-TDI in in parallel serial14
  15. 15. DFT for Boundary Scan TestRule #3 Level Shifter When Different Logic LevelRule #3.1: Test Access on EVERY TDI, TDO, TCK, TMS Test Access on EVERY TDI, TDO, TCK, TMS. (and TRST if the IC has TRST pin) U1 This is a MUST request for debug-purpose. U3 If possible, Put one access in interconnect pins, This can help to understand the out- U2 putting signal situation when debugging the interconnect test. TDI TDO TDI TDO TDI TDO TCK TMS TCK TMS TCK TMSRule #3.2 : Check IC’s Logic Level Put Level Shifter between ICs, If the ICs operate in different logic level. Don’t forget to put the TAP(TDI, TDO, TMS, TCK) pins into Logic-level shifter #3.1 #3.2Note : When we have >3 ICs in the chain, We may consider to Test Access Logic put jumpers in middle ICs TDI,TDO pins. This can help to bypass not-working Bscan IC, and still make the whole for TAP, Level chain work. and One shifter If putting a jumper on the board is not allowed, The ICT Level access in when ICs engineer can put a GP relay or direct wiring inside the fixture to bypass the middle IC. shifter interconnect in different pins logic levels.15
  16. 16. DFT for Boundary Scan Test Rule #4 Additional Access from BSDLRule #4.1: Special Access for Compliance_Patterns from BSDL file Some ICs have special enabling pins, These pins can be found in BSDL file. Search “Compliance_Patterns”. To see what pins need to be triggered for smoothly turn-on Bscan mode. In this example, The nodes: PWRGOOD, DPRSTPB, Need Test Access for keeping “high”Rule #4.2: Special requirements in DESIGN_WARNING message 1149.1 allows IC to have special notes in BSDL with DESIGN_WARNING message, User 16 needs to check this message to see
  17. 17. DFT for Boundary Scan TestRule #5 Access for Disabling Surrounding DevicesRule #5: Access for Disabling Surrounding Device TDI Experience showed :Without Bscan IC TDO TCK disabling the surrounding devices, TMS especially the CLK generator, the CLK Boundary IC sometimes, can not function under Bscan mode. Or functioning with CLK Gen R unstable/unpredictable errors. POWER_disable Therefore, We recommend to disable the surrounding devices, especially the “Clock Generator”. Access here to Disable CLK Gen For the disable pin, the designer need to put pull-up (or pull-down) resistor and a test access on it.17
  18. 18. DFT for Boundary Scan TestRule #6 Bscan Access on Bottom-SideRule #6:Pull BScan Access on Bottom- Not Probe from Upper Side Side of the Board Put the TDI, TDO, TCK, TMS, TRST access on Bottom-Side of the board, So that these pins will be probed from bottom part of the fixture. Due to shorter signal path and not- through transfer-pins, probing from bottom part of the fixture will have a better signal integrity, and more accurate for the probe to hit the test TDI TDO TCK TMS TRST pad. Experience showed: Probing TAP Probe from Bottom Side pins from bottom side, will result in a TAP access should be Test Pad, Do NOT thru Via hole, more stable Bscan Testing. Test Pad size should >30mils at least; with 100mils probe Some Bscan Validation “Connector”18 need to be on top side, That will be a
  19. 19. VTEP Family Innovation Connector High Speed Year Innovation SW No Test Access Version IC Signal Pin Connector (Sensitivit (Sensitivity) Solution GND Pin 1993 TestJET y) YES YES >20fF >20fF 2003 VTEP YES YES 5.3 >5fF >5fF 2005 iVTEP YES YES 5.42 <5fF >5fF 2007 VTEP v2.0 YES YES 7.0 YES NPM <5fF >5fF 2008 YES YES VTEP v2.0 Powered 7.2 YES YES Cover-Extend <5fF >5fF19
  20. 20. TestJET vs VTEP MDA with I1000 with TestJET VTEP(iVTEP) ICs: ICs: Tested Pins: 482 Tested Pins: 1168 Testable: 1201 Testable: 1201 Coverage:41% Coverage 2.36x better Coverage:97% Connectors: Connectors: Tested Pins: 260 Tested Pins: 445 VTEP σ = 0.3 Testable: 450 Testable: 450 Coverage:58% Coverage:98% Testjet σ = 1.7 DDR2 :Vcc/GND covered sATA :Vcc/GND covered Note: Testable pins =Total pins –Vcc-GND- No Access- same nail pins20
  21. 21. The Digital Way to Test Device is powered up Good Power Up Sequence Vcc Device under test Bscan Test Tree Test Lib Function 1 01 0 0 Digital Digital Receiver Driver Verified IC LIB/BSDL Minimized Noise Interference21
  22. 22. Comparison Analog Way: Digital Way: Boundary TestJET/VTEP Scan Coverage Good Good Test Time Moderate Fast 100% 100% for single IC <50% Test Access for IC chain Required Standard in Tester Need License in Tester No Cost USD1K more in fixture extra cost for fixture IC Type No restriction in IC type IC must be 1149.1-capable Noise Immunity Moderate Moderate to Good Programming Time Auto Generation <1hour 1-2 day Debug Effort Easy More Effort False Call Rate Moderate, Adjustable Low22
  23. 23. NEW !! Combining Analog VTEP + Digital BscanCover Extend TechnologyExtend Bscan Coverage fromBscan IC to Adjacent Non-Bscan Device to ICT tester … VTEP sensors Boundary Scan device Connector or other device Remove Test Access TD0 TDI TCK TMS Test Access pins23
  24. 24. Increasing Test In-System ProgrammableCoverage at ICT Device Solutions
  25. 25. What is ISP?The term In-System Programming (ISP) refers toprogramming of programmable devices after they aresoldered onto a PC board.This includes both FLASH and Programmable LogicDevices (PLDs) as well as other devices.25
  26. 26. FLASH & PLD market growth 20 3.5 18 3 16 14 2.5 Dollars (Billions) 12 Units (Billions) WOW ! 2 10 1.5 8 6 1 4 0.5 2 0 0 2009 2010 2011 2012 2013 2014 PLD $ FLASH $ PLD Units FLASH Units Flash memory is now found in 70% of PCBA‟s built today.26
  27. 27. In-System Programming Profile• Flash memory devices are used on more than 70% of PCBA‟s manufactured today.• Programmable Logic Devices (PLD, CPLD, SPLD, FPGA are used on more than 40% of PCBAs manufactured today.• Usage for both is growing rapidly.• Logistics issues are driving manufacturer‟s to program these devices after mounting onto PCBA‟s (In-System Programming). • Rapid production turn-around (time-to-market). • Reduced inventory. • Facilitate engineering changes. • Post manufacturing repair and reprogramming.27
  28. 28. What ISP Devices Can We Address with i3070? Type of Device Programmable on the i3070? FLASH YES. EPROMs/PROMs YES. But requires extra voltages on the board. CPLDs YES. FPGA (RAM based) YES, but why would you want to do this? Configuration EEPROMS YES. Serial EEPROMs YES. PAL/GAL YES, but it depends on the device.28
  29. 29. Description of Flash ISP features • Support of larger devices (>256Mbit) • Much faster first run time than Flash70 • Faster mature run time than Flash70 • Much smaller object file size • Much less testhead memory required • No dependency between repeat loop count and segment size. • Automatic repeat loop (go until end of data). • Flag bad checksums on data records (S-record and Intel Hex) • Summary information of data image compilation: – The number of bytes programmed – The number of bytes stripped (“FF stripping”) – The total number of segments – Compiler flags turned-on or off – The Minimum and Maximum addresses used29
  30. 30. Example of Summary Information30
  31. 31. Description of PLD ISP features • Ability to program PLDs directly from: – Serial Vector Format (SVF) file – Standardized Test And Programming Language (STAPL) file – Jam file – Jam Byte Code (JBC) file • No need to convert to PCF/VCL file(s). • Much Faster compile time. • Much less files to keep track of: VCL file plus data file. • Single test programming - no resistors in the fixture. • Print statements in Jam or STAPL files will output to BT-Basic window. • We can now program “non-F” Altera parts.31
  32. 32. Block Diagram showing Flash ISP Memory Vector Ram Sequence Ram Vector Ram MUX Directory Ram Sequence Ram Vector Ram Data i3070 Items in BLUE are found only in Translation Image Data Acceleration Control XTP card.32
  33. 33. How do we do it? FLASH Flash Software paradigm: • Pass address/data image file to testhead with programming algorithm information (we now have a Flash “Player”). • Results in MUCH smaller object file and, as a result, less time required for first run time download. • Changed method of downloading image and object files to testhead by bypassing the system card. • New software structure allows for easier support of new data file formats and Flash data image manipulation. • Two compiles happen “Behind the scenes” : – Convert data format to i3070 image – Create i3070 programming algorithm object file33
  34. 34. VCL syntax - Example of Flash ISPflash isp ! Instead of “flash” unitassign Data_Bus to pins 4,3,2,1 ... execute V1. . . segment hexadecimal “400”vector V1 repeat ! Automatic Loop set . . . execute V2 drive data Addrend vector execute V2 drive data My_Data. . . execute Writeflash assignments execute End_Cycle file “” srecord homingloop data My_Data to groups Data_Bus execute RY_Done exit if pass address Addr to groups Addr_Bus end homingloop eod reuse next Addrend flash assignments next My_Data. . . end repeat end segment end unit34
  35. 35. Process to convert existing Flash70 test to new Flash ISP test 1. Enable the Flash ISP software in the config file (enable flash isp). 2. Make a backup copy of the original file! 3. Change „flash‟ keyword to „flash isp‟. 4. Change „data/end data‟ block to „flash assignments‟ block: a. Change the „file‟ statement to new syntax. b. Point to Data bus group with „data‟ statement. c. Point to Address bus group with „address‟ statement. d. Make sure the “end-of-data” action is defined. As long as you do not have multiple different vectors trying to drive address or data, you should now be done (see “Limitations” section).35
  36. 36. Limitations - Flash ISP • Address bus width limited to 32-bit (4G addresses) • Data bus width limited to 128-bit if drive or receive data only or 64-bit if both drive and receive data (i.e., Data Polling). • Cannot drive Address and Data on the same vector (example, execute V1 drive data Address drive data Data). • Cannot have different vectors to drive address or data (e.g., execute V1 drive data Data, execute V2 drive data Data). • Entire Flash image must reside in testhead memory. • Cannot handle parameter passing (i.e., serial number, NIC, etc.). • Only one “flash assignments” block per test. This means only one data file can be accessed.36
  37. 37. Success Factors for Programming 1. Make sure you have proper testability: • Full access for Flash and disable nodes • Easy disable methods 2. Use Ground Plane in the fixture. 3. Specify TAP pins with “Critical” attribute in Board Consultant! 4. Make sure PLD programming data files were generated with Bscan chain defined. You can download the programs to create the SVF/Jam/STAPL files from the PLD vendor‟s web sites. 5. Remember, if you have an ECO to the data file for Flash ISP, you must recompile with the new data file.37
  38. 38. Questions and Answers Agilent Restricted March 2009Page 38
  39. 39. 39
  40. 40. Typical Debug Problems on Boundary Scan •Ground Bounce •Bad BSDL data file •Topology Errors (from CAD translation) •Standard Digital disabling problems From Mike Farrell40 Page 40
  41. 41. Ground Bounce Debug Ground Bounce • Cause: too many pins change state at once for the board and fixture‟s power & ground capability (Note: Use short wire fixtures with good grounding.) The board “ground” node spikes relative to tester ground which creates a signal spike at clock inputs. State machine jumps ahead due to unexpected spikes on clock input • Break up into tests with fewer pins transitioning – Max Connect option • Ground bounce suppression option • Potential issue of noise on the board – Voltage regulators one source. • Ground plane is a good choice for helping with this problem. • Twisted pair wiring might be needed. • Time for a scope on the TCK line. From Mike Farrell41 Page 41
  42. 42. Potential Problems With BSDL Files •The BSDL will not compile due to syntax issue(s) •Wrong boundary-scan register length – number of cells in the chain. •Wrong ID code value. •Pin order for a section is wrong (reversed). •The BSDL file does not match the actual silicon. •The part is non complicate with the 1149 standard – may require special vectors or pins to allow the boundary-scan section to work •The part has multiple boundary-scan chains internal to the part. Seeing more and more of this. •Wrong cell type assigned to the associated pin. •Instruction code is wrong. •Wrong or older BSDL file is being used. From Mike Farrell42 Page 42
  43. 43. 1149.6 – AC Signal Detection From IEEE Document “1149.6 IEEE Standard for Boundary Scan Testing of Advanced Digital Networks - Coverage on AC-coupled differential signals - Compliant to the IEEE 1149.6 standard - More designs are going hi-speed (> GHz) eg DDR3 - Uses more of these type of architecture Capacitors tested for presence Traces and pins tested for connectivity From Mike Farrell43 Page 43
  44. 44. Benefits of Advance Boundary-Scan •Quick and easy way to generate test model for complex device. •Use an industrial standard (1149). •Ability to break large devices into multiple tests to reduce test resource requirements. •Ability to chain number of devices together and test with a standard method. •When boundary-scan devices are chained, a method to help gain test coverage with reduced test access. •Programming ISP devices. •Potential to testing non boundary-scan devices with silicon nails. •Coverage Extend •Potential for running built in self test (BIST). •Will start seeing chips with built in measuring devices (embedded) that will be controlled by boundary-scan. •Potential for testing high speed lines with capacitance coupling (1149.6). From Mike Farrell44 Page 44