Analog Devices MAX1763 Product Info

• Up to 94% Efficiency
• +0.7V to +5.5V Input Voltage Range
• 1.1V Guaranteed Startup Input Voltage
• Up to 1.5A Output
• Fixed 3.3V Output or Adjustable (2.5V to 5.5V)
• 1MHz PWM Synchronous-Rectified Topology
• 1µA Logic-Controlled Shutdown
• Analog Gain Block for Linear-Regulator or Low-Battery Comparator
• Adjustable Current Limit and Soft-Start
• 1.5W TSSOP Package Available

The MAX1763 is a high-efficiency, low-noise, step-up DC-DC converter intended for use in battery-powered wireless applications. This device maintains exceptionally low quiescent supply current (110µA) despite its high 1MHz operating frequency. Small external components and a tiny package make this device an excellent choice for small hand-held applications that require the longest possible battery life.

The MAX1763 uses a synchronous-rectified pulse-width-modulation (PWM) boost topology to generate 2.5V to 5.5V outputs from a wide range of input sources, such as one to three alkaline or NiCd/NiMH cells or a single Lithium-ion (Li+) cell. Maxim's proprietary Idle Mode™ circuitry significantly improves efficiency at light load currents while smoothly transitioning to fixed-frequency PWM operation at higher load currents to maintain excellent full-load efficiency. Low-noise, forced-PWM mode is available for applications that require constant-frequency operation at all load currents. The MAX1763 may also be synchronized to an external clock to protect sensitive frequency bands in communications equipment.

The MAX1763 includes an on-chip linear gain block that can be used to build a high-power external linear regulator or as a low-battery comparator. Soft-start and current limit functions permit optimization of efficiency, external component size, and output voltage ripple.

The MAX1763 is available in a space-saving 16-pin QSOP package or a high-power (1.5W) 16-pin TSSOP-EP package.

Applications

• Digital Cordless Phones
• Handheld Instruments (PDAs, Palmtops)
• Palmtop Computers
• PCS Phones
• Personal Communicators
• Wireless Handsets