MAX1744

 High-Voltage Operation (up to 36V IN)
Efficiency >90%
Output Power Capability Exceeds 50W
10-Pin Max Package
Low-Dropout Voltage
100% (max) Duty Cycle
90A Quiescent Current
4A Shutdown Current
Up to 330kHz Switching Frequency
Output Voltage
        5V or 3.3V (MAX1744)
        Adjustable 1.25V to 18V (MAX1745)
Current-Limited Control Scheme

IN, EXT, SHDN to GND...........................................-0.3V to +38V
VH to GND............................................................-0.3V to +34V
VH, EXT to IN..........................................................-7V to +0.3V
CS, OUT to GND ...................................................-0.3V to +20V
FB, 3/5, REF to GND ....................................-0.3V to (VL + 0.3V)
VL to GND.................................................................-0.3V to 6V
Continuous Power Dissipation (TA = +70°C)
  10-Pin MAX (derate 5.6mW/°C above 70°C) .............444mW
Operating Temperature Range
MAX174_EUB .................................................. -40°C to +85°C
MAX174_AUB ................................................ -40°C to +125°C
Junction Temperature...................................................+150°C
Storage Temperature Range ......................... -65°C to +150°C
Lead Temperature (soldering, 10s) ............................. +300°C

Stresses beyond those listed under "Absolute Maximum Ratings" may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability.

The MAX1744/MAX1745 are step-down DC-DC controllers capable of handling up to 36V inputs. These parts use a proprietary current-limited control scheme for excellent light- and full-load efficiency, while their 330kHz (max) switching frequency permits small external components for space-critical applications.Operation to 100% duty cycle permits the lowest possible dropout voltage.

The MAX1744 contains an internal feedback network that provides a pin-selectable output voltage of either 3.3V or 5V. The MAX1745 uses an external feedback network to generate an adjustable output voltage between 1.25V and 18V.

The MAX1744/MAX1745 are available in a space-saving 10-pin MAX package.