High Efficiency, 140V 250mA Step-Down Regulator

The LTC3638 is a high efficiency step-down DC/DC regulator with internal power switch that draws only 12μA typical DC supply current while maintaining a regulated output voltage at no load.

The LTC3638 can supply up to 250mA load current and features a programmable peak current limit that provides a simple method for optimizing efficiency and for reducing output ripple and component size. The LTC3638’s combination of Burst Mode® operation, integrated power switch, low quiescent current, and programmable peak current limit provides high efficiency over a broad range of load currents.

With its wide input range of 4V to 140V and programmable overvoltage lockout, the LTC3638 is a robust regulator suited for regulating from a wide variety of power sources. Additionally, the LTC3638 includes a precise run threshold and soft-start feature to guarantee that the power system start-up is well-controlled in any environment. A feedback comparator output enables multiple LTC3638s to be connected in parallel for higher current applications.

The LTC3638 is available in a thermally enhanced high voltage-capable 16-lead MSE package with four missing pins.

Applications

* Industrial Control Supplies

* Medical Devices

* Distributed Power Systems

* Portable Instruments

* Battery-Operated Devices

* Avionics

* Automotive

* Wide Operating Input Voltage Range: 4V to 140V

* Internal Low Resistance Power MOSFET

* No Compensation Required

* Adjustable 20mA to 250mA Maximum Output Current

* Low Dropout Operation: 100% Duty Cycle

* Low Quiescent Current: 12μA

* Wide Output Range: 0.8V to VIN

* 0.8V ±1% Feedback Voltage Reference

* Precise RUN Pin Threshold

* Internal or External Soft-Start

* Programmable 1.8V, 3.3V, 5V or Adjustable Output

* Few External Components Required

* Programmable Input Overvoltage Lockout

* Thermally Enhanced High Voltage MSOP Package