MAX1709EUI+

The MAX1709 sets a new standard of space savings for high-power, step-up DC-DC conversion. It delivers up to 20W at a fixed (3.3V or 5V) or adjustable (2.5V to 5.5V) output, using an on-chip power MOSFET from a +0.7V to +5V supply. Fixed-frequency PWM operation ensures that the switching noise spectrum is constrained to the 600kHz fundamental and its harmonics, allowing easy postfiltering for noise reduction. External clock synchronization capability allows for even tighter noise spectrum control. Quiescent power consumption is less than 1mW to extend operating time in battery-powered systems. Two control inputs (ONA, ONB) allow simple push-on, push-off control through a single momentary pushbutton switch, as well as conventional on/off logic control. The MAX1709 also features programmable soft-start and current limit for design flexibility and optimum performance with batteries. The MAX1709 is supplied in both a high-power TSSOP package, which allows a 10A switch current and a 4A output, and a narrow SO package, which supplies a 2.4A output with a switch rated at 6A. Although the narrow SO device has a lower RMS switch rating, it has the same peak switch current rating as the TSSOP device, and so can supply 4A loads intermittently. The MAX1709 step-up converter offers high efficiency and high integration for high-power applications. It operates with an input voltage as low as 0.7V and is suitable for single- to 3-cell battery inputs as well as 2.5V or 3.3V regulated supply inputs.

Applications

• Routers, Servers, Workstations, Card Racks
• Local 2.5V to 3.3V or 5V Conversion
• Local 3.3V to 5V Conversion
• 3.6V or 5V RF PAs in Communications Handsets

Key features

• Integration Reduces External Component Count to Save Space
• On-Chip 10A Power MOSFET
• 5V, 4A Output from a 3.3V Input
• Fixed 3.3V or 5V Output Voltage or Adjustable (2.5V to 5.5V)
• Input Voltage Range Down to 0.7V
• Constant Frequency Reduces Post-Filtering
• Low-Noise, Constant-Frequency Operation (600kHz)
• Synchronizable Switching Frequency (350kHz to 1000kHz)
• Lower Power Consumption Extends Battery Life
• 1mW Quiescent Power