ZHCSOQ8A August 2021 – October 2021 LM5158-Q1 , LM51581-Q1
PRODUCTION DATA
The device provides cycle-by-cycle peak current limit protection that turns off the internal MOSFET when the inductor current reaches the current limit threshold (ILIM). To avoid an unexpected hiccup mode operation during a harsh load transient condition, it is recommended to have more margin when programming the peak-current limit.
Boost converters have a natural pass-through path from the supply to the load through the high-side power diode (D1). Because of this path and the minimum on-time limitation of the device, boost converters cannot provide current limit protection when the output voltage is close to or less than the input supply voltage. The minimum on time is shown in Figure 8-15 and is calculated as Equation 8.