SNVSCU9A May 2025 – November 2025 TPS7H4012-SEP , TPS7H4013-SEP
PRODMIX
Sometimes, the HS1 current limit is not sufficient to protect the device. For example, a short circuit may be so aggressive that even if the high side is only on for the minimum on time, tON, the current would continue to rise. To mitigate this risk, the TPS7H401x implements a secondary overcurrent protection in the form of high-side overcurrent protection 2 (HS2).
The HS2 current limit is reached when the current through the high side MOSFET meets or exceeds IOC_HS2. To prevent sustained current increase, the next four high-side cycles are skipped while the low side MOSFET remains on in order to discharge the inductor. The simplified waveforms of this operation are shown in Figure 9-10.
The high side 2 overcurrent protection (HS2) threshold value is typically 11.8A for the TPS7H4012 and 6.8A for the TPS7H4013.
Similar to the IOC_HS1 current limit, the IOC_HS2 limit threshold is measured in an open loop configuration due to testability limitations while actual short circuit events are dynamic and in closed loop