ic dc-dc转换icpt1109

pt1109

1.5a,24v,380khz step-down converter

general description

the pt1109 is a monolithic step-down switch mode regulator with a built in internal power mosfet. it achieves 1.5a continuous output current over a wide input supply range with excellent load and line regulation. current mode operation provides fast transient response and eases loop stabilization. fault condition protection includes cycle-by-cycle current limiting and thermal shutdown. in shutdown mode the regulator draws 23μa of supply current.

the pt1109 requires a minimum number of readily available standard external components

features

¨        1.5aoutput current

¨        0.5ω internal power mosfet switch

¨        stable with low esr output ceramic capacitors

¨        up to 95% efficiency

¨        23μa shutdown mode

¨        fixed 380khz frequency

¨        thermal shutdown

¨        cycle-by-cycle over current protection

¨        wide 4.75v to 24v operating input range

¨        output adjustable from 1.22v to 18v

¨        programmable under voltage lockout

¨        available in 8-pin sop8 packages

applications

¨        pc monitors

¨        distributed power systems

¨        batterycharger

¨        pre-regulator for linear regulators