Torex Semiconductor has a dual channel synchronous step-down dc-dc converter plus a voltage detector with delay circuit built-in.

The dc-dc converter block operates from a supply voltage range between 2.5V and 5.0V, providing output voltages that can be factory set in 100mV increments between 1.2V and 4V per channel and output currents up to 800mA.

It incorporates a P-channel 0.35Ω (typ) mosfet driver and a synchronous N-channel 0.35Ω (typ) switching transistor.

By minimising on-resistance of the built-in transistors, the XC9515 series can deliver efficiency of up to 95% (VIN=5V, VOUT=3.3V) and stable output current of up to 800mA per channel. The switching frequency of 1MHz helps to reduce the size of the necessary inductors.

All devices offer a variety of safety features including short-circuit protection, thermal shutdown and integral latch (over-current limit). An under-voltage lock out (UVLO) feature is also incorporated which shuts down the supply if the input voltage falls below 1.8V, thereby preventing anomalous operation and ensuring a normal start after power dips.

The voltage detector block can be used to set delay time freely by connecting an external capacitor. Voltage detect range is between 2V and 5.5V (+/-2%) and with the manual reset function the device can output a reset signal at any time.

More information: www.torex-europe.com