0.8A, Low-Noise, 1MHz, Step-Up DC-DC Converter

The MAX1760/MAX1760H are high-efficiency, low-noise, step-up DC-DC converters intended for use in battery-powered wireless applications. They combine low quiescent supply current (100µA) with a high 1MHz operating frequency. Small external components and tiny 10-pin TDFN and µMAX® packages make this device an excellent choice for small hand-held applications. The MAX1760 is activated by a logic-low active-low ON signal while the MAX1760H is activated by a logic-high ON input.

Both devices use a synchronous-rectified pulse-width-modulation (PWM) boost topology to generate 2.5V to 5.5V outputs from a wide range of inputs, such as 1 to 3 alkaline or NiCd/NiMH cells or a single lithium-ion (Li+) cell. Proprietary Idle-Mode™ circuitry significantly improves light-load efficiency and smoothly transitions to fixed-frequency PWM operation at higher load currents.

Low-noise, forced-PWM mode is available for applications requiring constant-frequency operation at all load currents. PWM operation can also be synchronized to an external clock to protect sensitive frequency bands in communications equipment. Analog soft-start and adjustable current limit permit optimization of efficiency, external component size, and output voltage ripple.

Applications

* Digital Cordless Phones * Handheld Instruments * Palmtop Computers * PCS Phones * Personal Communicators * Two-Way Paging * Wireless Handsets

* Up to 94% Efficiency

* 0.7V to 5.5V Input Range

* Up to 800mA Output

* Fixed 3.3V Output (or Adjustable from 2.5V to 5.5V)

* PWM Synchronous-Rectified Topology

* Low-Noise, Constant-Frequency Operation (1MHz)

* 0.1µA Logic-Controlled Shutdown

* Synchronizable Switching Frequency

* Adjustable Current Limit

* Adjustable Soft-Start

* 10-Pin µMAX Package

* 10-Pin 3mm x 3mm TDFN Package