SLVK117 October 2022 TPS7H2221-SEP
The primary concern for the TPS7H2221-SEP is the robustness against the destructive single-event effects (DSEE): single-event latch-up (SEL), single-event burnout (SEB), and single-event gate rupture (SEGR). In mixed technologies such as the BiCMOS process used on the TPS7H2221-SEP, the CMOS circuitry introduces a potential for SEL susceptibility.
SEL can occur if excess current injection caused by the passage of an energetic ion is high enough to trigger the formation of a parasitic cross-coupled PNP and NPN bipolar structure (formed between the p-sub and n-well and n+ and p+ contacts) [1,2]. The parasitic bipolar structure initiated by a single-event creates a high-conductance path (inducing a steady-state current that is typically orders-of-magnitude higher than the normal operating current) between power and ground that persists (is “latched”) until power is removed, the device is reset, or until the device is destroyed by the high-current state. The TPS7H2221-SEP was tested for SEL at a maximum recommended input voltage of 5.5-V and a load of 1.25-A. Testing was done with a discrete power resistor of 4.4 Ω or a Chroma E63600 ELoad in Constant Resistance (CR) mode. During the SEL testing a Closed-Loop PID controlled heat gun (MISTRAL 6 System (120V, 2400W)) was used to heat the device to 125°C. A FLIR (FLIR ONE Pro LT) thermal camera was used to validate die temperature to ensure the device was being accurately heated. The device exhibited no SEL with heavy-ions with up to LETEFF = 46.8 MeV·cm2/mg, flux ≈105 ions/cm2·s and fluences of ≈107 ions/cm2.
The TPS7H2221-SEP was evaluated for SEB/SEGR at a load of 1.25-A and an input voltage of 5.5-V. The device was tested under enabled and disabled modes. During the SEB/SEGR testing, not a single current event was observed, demonstrating that the TPS7H2221-SEP is SEB/SEGR-free up to LETEFF = 46.8 MeV·cm2/mg at a flux of ≈105 ions/cm2·s, fluences of ≈107 ions/cm2, and a die temperature of ≈25°C.
The TPS7H2221-SEP was characterized for SET at flux of ≈104 or 105 ions/cm2·s, fluences of ≈3 x 106 or 107 ions/cm2, and a die temperature of about 25°C. The device was characterized at VIN = 1.8-V, 3.3-V, and 5-V with varying loads of 100-mA to 1.25-A. Under these conditions all recorded VOUT voltage excursions self-recover with no external intervention.