JAJSJT8C May 2020 – June 2021 TPS543620
Negative current is sensed in the low-side MOSFET while it is conducting after a short blanking time to allow noise to settle. Whenever the low-side negative overcurrent threshold is exceeded, the low-side MOSFET is immediately turned off. The next high-side MOSFET turnon is determined by the clock and PWM comparator. The negative overcurrent threshold minimum value is 2.95 A. Similar to the positive inductor current protections, the actual value of the inductor current when the current sense comparators trip will be a function of the current ramp rate. As a result the current at which the negative inductor current limit takes effect can be slightly more negative than specified.