ZHCSMU8C March 2020 – July 2021 TPS54JA20
PRODUCTION DATA
The device has a fixed, cycle-by-cycle negative current limit. Similar with the positive overcurrent limit, the inductor current is monitored during the on-time of the low-side FET. To prevent too large of negative current flowing through the low-side FET, when the low-side FET detects –10-A current (typical threshold), the device turns off the low-side FET and then turns on the high-side FET for a proper on-time (determined by VIN/VO/fSW). After the high-side FET on-time expires, the low-side FET turns on again.
The device should not trigger the –10-A negative current limit threshold during nominal operation unless too small inductor value is chosen or the inductor becomes saturated. This negative current limit is utilized to discharge output capacitors during an output OVP or an OOB event. See Section 7.3.12 and Section 7.3.13 for details.