SC412AMLTRT

Product Summary

The SC412A is a versatile, constant on-time synchronous   buck, pseudo  ? xed-frequency, PWM controller intended   for notebook computers and other battery operated   portable devices. The SC412A contains all the features   needed to provide cost-effective control of switch-mode   power outputs.  The output voltage is programmable from 0.75 to 5.25   volts using external resistors.  Switching frequency is   internally preset to 325kHz.  Additional features cycleby-cycle current limit, voltage soft-start, under-voltage   protection, programmable over-current protection, soft   shutdown, automatic power save and non-overlapping   gate drive.  The SC412A also provides an enable input   and a power good output

Parametrics

The constant on-time topology provides fast, dynamic   response. The excellent transient response means that   SC412A based solutions require less output capacitance   than competing  ? xed-frequency converters.  Switching   frequency is constant until a step in load or line voltage   occurs, at which time the pulse density and frequency   will increase or decrease to counter the change in   output voltage.  After the transient event, the controller   frequency returns to steady state operation.  At light loads,   the automatic power save mode reduces the switching   frequency for improved ef? ciency.

Features

?  V  BAT   Range 3V to 25V  ? Soft-Shutoff at Output  ? Current Sense Using  Low-Side R  DS(ON)    or Resistor   Sensing with Adjustable Cycle-by-Cycle Current Limit  ? Fixed-Frequency 325kHz  ? Constant On-Time for Fast Dynamic Response and   Reduced Output Capacitance  ? Automatic Smart Power Save  ?  ? Internal Soft-Start   ? Over-Voltage/Under-Voltage Fault Protection   ? Power Good Output  ?  1μA Typical Shutdown Current  ? Tiny 3x3mm, 16 Pin MLP, Lead-free Package  ? Low External Part Count  ? Industrial Temperature Range  ? 1% Internal Reference  ? 1A/3A Non-Overlapping Gate Drive with SmartDrive?   ? High Ef? ciency > 90%  ? Fully WEEE and RoHS Compliant

Diagrams