SLVSFW3 March 2022 TPS629203-Q1
PRODUCTION DATA
The TPS629203-Q1 is protected against overload and short circuit events. If the inductor current exceeds the current limit, ILIM_HS, the high-side switch is turned off and the low-side switch is turned on to ramp down the inductor current. The high-side FET turns on again only if the current in the low-side FET has decreased below the low-side current limit threshold, ILIM_LS.
Due to internal propagation delay, the actual current can exceed the static current limit during that time. The dynamic current limit is given in Equation 1.
where:
The current limit can exceed static values, especially if the input voltage is high and very small inductances are used. The dynamic high-side switch peak current can be calculated as follows:
The TPS629203-Q1 also includes a low-side negative current limit (ILIM:SINK) to protect against excessive negative currents that can occur in forced PMW mode under heavy to light load transient conditions. If the negative current in the low-side switch exceeds the ILIM:SINK threshold, the low-side switch is disabled. Both the low-side and high-side switches remain off until an internal timer re-enables the high-side switch based on the selected PWM switching frequency.