The Micrel MIC2174 is a synchronous, digitally modified, constant on-time pulse-width modulation (PWM) buck controller. These controllers are targeted for cost sensitive applications requiring high performance such as set-top boxes, gateways, routers, computing peripherals, and telecom/networking equipments.

The MIC2174 operates over an input supply range of 3V to 40V, and is independent of the IC supply voltage. The MIC2174 operates at a fixed frequency of 300kHz and is capable of supplying 25A output current. The output voltage is adjustable from 0.8V to 0.86V IN.

A unique Hyper Speed Control™ architecture allows for ultra fast transient response while reducing the output capacitance and also makes High V IN/Low V OUT operation possible. The MIC2174 utilizes an architecture which is constant Ton ripple controlled. An UVLO is provided to ensure proper operation under power-sag conditions to prevent the external power MOSFET from overheating. A soft start is provided to reduce inrush current. Foldback current limit and “hiccup” mode short-circuit protection ensure FET and load protection.

The MIC2174 is available in a 10-pin MSOP (MAX1954A-compatible) package with a junction operating range from –40 °C to +125 °C.

All support documentation can be found on Micrel’s web site at: www.micrel.com.