6 Test Setup and Procedures

There were two input supplies used to power the TPS7H5020-SEP which provided V_IN and EN. The V_IN for the device was provided via Ch. 3 of an N6705C power module and ranged from 4.5V to 14V for SEL, SEB/SEGR, and SET testing. The EN of the device was driven by an E36311A power supply and was either forced to 0V or 5V to enable or disable the device. A NI PXIe-6341 DAQ was used to drive V_SNS and V_COMP. V_LDO had 3 programmable voltages, 4.5V, 5V, or 5.5V and were selected by closing relays to connect to a feedback network on the EVM to select the required V_LDO voltage. Input ranges for the different modes and switching frequencies are shown below. Note that the P_VIN column denotes whether or not P_VIN (the driver stage input) was tied to V_IN or V_LDO.

The primary signal monitored during testing was GATE (OUTH and OUTL tied together on the EVM) and this was done so using a PXIe-5110 triggering using a pulse-width trigger at 20%.

All equipment was controlled and monitored using a custom-developed LabVIEW? program (PXI-RadTest) running on a HP-Z4 desktop computer. The computer communicates with the PXI chassis via an MXI controller and NI PXIe-8381 remote control module.

Table 6-2 shows the connections, limits, and compliance values used during the testing. Figure 6-1 shows a block diagram of the setup used for SEE testing of the TPS7H5020-SEP.

Note that only the relay for the correct feedback network was driven by the PXIe-6341 for V_LDO, not the actual V_LDO voltage.

All boards used for SEE testing were fully checked for functionality. Dry runs were also performed to verify that the test system was stable under all bias and load conditions prior to being taken to the test facilities. During the heavy-ion testing, the LabVIEW control program powered up the TPS7H5020-SEP device and set the external sourcing and monitoring functions of the external equipment. After functionality and stability was confirmed, the beam shutter was opened to expose the device to the heavy-ion beam. The shutter remained open until the target fluence was achieved (determined by external detectors and counters). During irradiation, the NI scope cards continuously monitored the signals. When the output exceeded the pre-defined pulse-width trigger, a data capture was initiated. No sudden increases in current were observed (outside of normal fluctuations) on any of the test runs and indicated that no SEL or SEB/SEGR events occurred during any of the tests.

Figure 6-1 Block Diagram of the SEE Test Setup for the TPS7H5020-SEP