The OPA4H014-SEP HDR exposure was performed on biased devices in a Co60 gamma cell at TI SVA facility in Santa Clara, California. The unattenuated dose rate of this cell is 50-300 rad(Si) / s. After exposure, the devices were packed in dry ice and returned to TI Dallas for a full post irradiation electrical evaluation using Texas Instruments ATE. ATE guard band test limits are set within data sheet electrical specifications to maintain a minimum Cpk and test error margin based on initial qualification and characterization data. Post irradiation measurements were taken within 30 minutes of removal of the devices from the dry ice container. The devices were allowed to reach room temperature prior to electrical post radiation measurements.

The OPA4H014-SEP LDR exposure was performed on biased and unbiased devices in a Co-60 gammacell under a 10-mrad(Si) / s exposure rate. The dose rate of the irradiator used in the exposure ranges from less than 10 mrad(Si) / s to a maximum of approximately 84 rad(Si)/s, determined by the distance from the source. For the LDR (10 mrad(Si) / s) exposure, the test box was positioned approximately 2 m from the source. The exposure boards are housed in a lead-aluminum box (as specified in MIL-STD-883 TM 1019.9) to harden the gamma spectrum and minimize dose enhancement effects. The irradiator calibration is maintained by Logmire Laboratories using Thermoluminescence Dosimeters (TLDs) traceable to the National Institute of Standards and Technology (NIST) and the dosimetry was verified using TLDs prior to the radiation exposures. After dosage to each incremental, specified test level, devices were electrically tested at TI Dallas using Texas Instruments ATE. The devices were then returned to the irradiation facility to continue to be dosed to the next level, until the maximum exposure level of 30 krad(Si) was reached.