SNVSBJ0B December 2019 – August 2021 LM5170
PRODUCTION DATA
The internal 25-µA current source and a single external resistor RIPK establish a voltage at the IPK pin to program the cycle-by-cycle current limit threshold. To set the inductor peak current limit value to IPK, RIPK must satisfy Equation 13:
IPK must be greater than the inductor peak current at full load, and lower than the rated saturation current of the inductor, Isat.
When the IPK pin voltage is greater than 4.5 V, either from a very large RIPK value or the pin being open or some other reason, an internal monitor circuit shuts down the switching. This prevents the LM5170 from operating with erroneous peak current limit threshold.