High Sense-Current Source

Particular thermal test devices and test methods may require junction-sense-currents higher than 50mA.  Test methods that use RdsOn as the temperature sensitive parameter (such as GaN MOSFETs) as well as large SCRs, Triacs, and diodes generally require junction-sense-currents higher than 50mA. This product provides switch-selectable sense currents of 250, 500, 1000, and 2500mA on a single Tj sense channel. It is designed for convenient use during junction calibration as well as all types of thermal test procedures. It is completely plug-compatible with all Analysis Tech thermal test fixtures and utilizes the same familiar user-interface procedures. Additional connectors for the higher sense current setup are included.

The forward resistance of the a MOSFET channel, commonly called RdsOn for the resistance, drain-to-source in full ON (saturated) condition, is typically junction-temperature dependent.  This dependency can be calibrated and used as the temperature sensitive parameter (TSP) in place of the usual diode forward voltage parameter.  This method is particularly useful with devices such as GaN MOSFETs that do not offer a diode-like junction for the TSP.  Since the sensitivity of the RdsOn TSP depends directly on magnitude of the sense current, sense currents of 500mA to 2500mA are typically required for accurate thermal testing with the RdsOn method.

Thryristors (SCRs and Triacs) with higher current capacity typically require higher gate-turn-on-currents than for smaller devices. Ideally, the Tj sense current used for thermal testing of thyristors is greater than the minimum gate-turn-on-current, so that the device is maintained in the ON condition. Since the Thermal Analyzer offers a maximum selectable sense current of 50mA, testing thristors with gate-turn-on currents greater than 50mA, requires the use of the High Sense Current Source. When testing large doides, especially schottky devices, higher sense currents can be needed for improved linearity of the Tj calibration parameters and for control of potentially overly-large measurement delays. The High Sense Current Source fills these requirements. Simple instructions ensure ease and convenience of operation. The source requires AC power and is available in either 110 or 220VAC models.

Ordering Information
Part Number: Hi-Sense-xxx where xxx is the AC supply voltage (110VAC, 50/60Hz or 220VAC 50/60Hz).  Custom orders welcome.