Rjc Liquid Cooled Test Fixture

The Analysis Tech R_jc Liquid Cooled Test Fixture is a high performance liquid-cooled heat sink with convenient electrical connections to the device-under-test. This fixture is ideally suited for measuring junction-to-case thermal resistance for all device types including IGBT modules and large MOSFET packages, and is well-suited for JEDEC 51-14 method testing. Temperature controlled coolant water must be supplied to the fixture from a recirculating chiller. Drip-free quick-connect hose fittings are provided for convenient connection of the coolant hoses.

A top-mounted combination plug/screw connector provides high-current heating-power connections to the device-under-test. The side-mounted edge-card connector provides duplicate low-current terminals, convenient for part-specific wiring and kelvin connections. This design allows the fixture to be quickly reconfigured for any part-type by swapping the part-specific, two-connector wiring harness. The backside case temperature of the device-under-test is sensed with a built-in spring loaded TC Sensor. Additionally, a thermocouple port is also provided for measuring the coolant inlet temperature as specified in JEDEC 51-14.

The device-under-test is clamped to the heat sink surface with a special pneumatic clamp, shown above. The pneumatic clamp offers a regulated and measured clamping force that will not change with temperature induced dimensional changes of the sample. The air cylinder used is a special air-balance cylinder with fluidic bearing that provides very accurate force measurement and control. For larger packages, convenient tapped holes (10-32 size) are provided to accommodate many common device/module footprints. The positioning jig is also provided for easy and consistent placement of devices with respect to the case thermocouple.

Rjc-Liquid Performance Specifications

R_{Heat Sink} = (T_Plate - T _{Inlet Water}) / Power