ZHCSFE3B March 2016 – November 2017 LM5161
PRODUCTION DATA.
The feedback voltage at the FB pin is compared to the SS pin voltage VSS. In normal operation when the output voltage is in regulation, an ON-time period is initiated when the voltage at FB pin falls below VSS. The high-side buck switch stays on for the ON-time one-shot period causing the FB voltage to rise. After the on-time period expires, the high-side switch will remain off until the FB voltage falls below VSS. During start-up, the FB voltage is below VSS at the end of each on-time period and the high-side switch turns on again after the minimum forced off-time of 170 ns (typical). When the output is shorted to ground (FB = 0 V), the high side peak current limit is triggered, the high-side FET is turned off, and remains off for a period determined by the current limit OFF-time one-shot. See the Current Limit section for additional information.