Phase 12 Application Features
Multiple Sense-Junction Channels
Up to eight junction temperatures can be simultaneously sensed for testing devices with multiple junctions and for characterizing multi-chip packages or modules. In multiple-die packages, the die-to-die heating (thermal cross-coupling) must be measured to accurately characterize these type of packages. For testing functional integrated circuits (ICs), multiple sense junctions offer validation of the junction temperature (Tj) readings in instances where some of the Tj sense connections are subject to the spurious electrical effects of other portions of the IC circuitry. When testing hybrids and large-die ICs, multiple sense junctions can reveal temperature distributions that occur when substantial temperature variations exist within the test device. Multiple sense channel applications include:
- Multi-die devices where multiple heat sources may exist
- Thermal cross-coupling associated with multi-chip devices
- Larger devices which may exhibit substantial temperature gradients during normal powered operation
Multiple sense channels also permit the calibration of up to 8 sense junctions simultaneously for faster calibration through-put.
Batch Mode and Bin Sorting for Power Pulse Testing
Accurate and rapid screening of device thermal characteristics can dramatically enhance production-device reliability. Die Attachment testing provides an excellent gauge of the chip attachment-quality in terms of the device impedance. The Phase 12 Thermal Analyzer provides programmable relay drivers for controlling external devices during Power Pulse Testing. These drivers offer the following capabilities:
- switching between test points in hybrid circuit test fixtures for multiple sequenced tests
- manual or automatic handler controls bin sorting based on die attachment test results
The test switching capability of the Thermal Analyzer allows one test fixture to carry all the test connections or test-point probes for a batch of tests required for testing complex hybrids. Thus all significant die attachments on a hybrid can be tested with one insertion and one test initiation.
Bin sorting is utilized in die attach testing to rapidly sort devices based on die-attachment quality. The bin sorting control can be used with manual insertion testing or with automatic component transfer systems which would insert devices to be tested into test fixtures and subsequently eject the tested device into one of up to eight bins. (see Die Attach Testing in Production Environments)
Accessory Equipment Control Ports
Frequently, device thermal performance must be evaluated over a range of external conditions. Such conditions might include cooling air flow, ambient operating temperature, coolant flow rate, or the heating supply voltage. The Thermal analyzer can control accessory test equipment via USB, IEEE, or serial communication to achieve integrated batch testing under a wide range of external conditions. The Analysis Tech accessory Batch Switching Module provides a convenient means to switch the device-under-test so that many devices can be tested sequentially in batch mode.
The simple setup and control procedures of the Thermal Analyzers allow the test engineer to initiate up to 200 tests in batch mode. Tests are successively executed automatically: as a test reaches completion, the external condition is incremented and the test cycle repeated until the batch of tests is completed. Once these batch tests have begun, data reporting and accessory equipment control are automatically coordinated.