Function Description (Cont.)
 
Over-Current Protection (Cont.)
When OCSET PIN is floating, the VOCSET will be pulled high and the over current threshold will be the internal
default value 0.25V. When the voltage drop across the lower MOSFET’s RDS(ON) is larger than 0.25V, an over-cur-
rent condition is detected, the controller will shutdown the IC directly, and latch the converter’s output.
 
Over Voltage Protection
The FB pin is monitored during converter operation by its own Over Voltage(OV) comparator. If the FB voltage is
over 135% of the reference voltage, the controller will make Low-Side gate signal fully turn on until the fault
events are removed.
Under Voltage Protection
The FBL pin is monitored during converter operation by its own Under Voltage (UV) comparator. If the FBL voltage
drop below 50% of the reference voltage (50% of 0.8V =0.4V), a fault signal is internally generated, and the de-
vice turns off both high-side and low-side MOSFET and the converter’s output is latched to be floating. The con-
troller will shutdown the IC directly.
 
Shutdown and Enable
Pulling low the FS_DIS pin near GND by an open drain transistor or other pull-down device (<1k. impedance)
will shutdown both regulators. Upon release of the FS_DIS pin, it will enable both outputs back into regulation. In
shutdown mode, the UGATE and LGATE turn off and pull to PHASE and GND respectively.