Limited access testing using IEEE1149.1 standard are now an essential part of manufacturing test strategy for complex and high node count digital boards. The Boundary scan tools (Scan Pathfinder) provided by Teradyne for the 228x and TestStation series of In-Circuit testers are dedicated tools that rely on the tester hardware for test pattern delivery and diagnostics. For sophisticated boundary scan applications such as Interconnect and Cluster testing, flash and ISP programming, the dedicated tools may not provide the necessary power, speed or flexibility. The integration of the stand-alone Boundary Scan tools with the Teradyne ICT can enhance the system capability and provide access to additional tools. The integration strategy provides the user with a common platform and portability of test patterns from stand-alone to ICT and later-on to functional test and depot test station.
Seamless integration of stand-alone Boundary San tools (BST) with Teradyne platforms has been tried unsuccessfully by many BST suppliers in the past, due to long path between the ICT test fixture interface and the BST controller in the PC. In order to get around the interface problems, the integration has been done, using separate PC, with specialized Pods directly interfacing with the test fixture etc. Operational reliability and test repeatability has been a common challenge and dramatic reduction in TCK rate the only answer. Therefore effecting throughput and practicality of this strategy and many have given-up trying.
Acculogic proven and patented Adaptive Clocking™ technology completely eliminates the effects of the long distance between the BST controller and the ICT test fixture interface therefore removing the hardware obstacle to seamless integration of Acculogic Boundary Scan tools with all Teradyne platforms.
Acculogic BST systems can be fully integrated with Teradyne 228x, TestStation 1xx, Pilot Flying Prober, Geneva and Versa functional test systems. Acculogic run time software through use of DLL provides seamless and transparent integration of the boundary scan test and programming with the system operating software.
Option 1 – Direct Backplane Access
The option 1 provides the total integration of Acculogic Bscan system with the Teradyne 228x/TestStation systems. Acculogic ScanMaster™ Boundary Scan controller is installed in any of the available PCI slots of the system controller PC, then the 4 BST signals (TCK, TMS, TDI and TDO) are routed through the external instruments access points to the Analog In-Circuit Test Module of the GR system to the test fixture receiver. The BST signals are available at the fixture receiver to be wired to targets BST port.
Boundary Scan Performance:
* The TCK is limited by the GR system backplane bandwidth (manufacturer specifies 5MHz).
Option 2 – Direct Fixture access
- TCK rate = 12 MHz *
- Data rate ~ up to 12 Mbits/second
For applications that require temporary integration, the BST signals can be routed from the ScanMaster™ directly to the test fixture through a DB25 type connector. The advantage of this approach, is simplicity, better signal path integrity for higher speed operation and requires fewer system resources.
Boundary Scan Performance:
- TCK rate = 25 MHz *
- Data rate ~ up to 25 Mbits/second
Once the test and programming applications have been developed and fully debugged using a standalone system, then final routines are called from within the Teradyne software environment using Acculogic ScanManager™
The Boundary Scan system fully supports: