Analog Devices MAX17557 Product Info

• Wide Range of Operation
  • Wide 4.5V to 60V Input Voltage Range
  • Wide 0.8V to 24V Output Voltage Range
  • R_SENSE or Inductor DCR Current-Sensing
  • 100kHz to 2.2MHz Adjustable Frequency with External Clock Synchronization
  • Available in a Lead (Pb)-Free 20-Pin, 4mm x 4mm TQFN-EP Package
• Enhances Power Efficiency
  • Low-Impedance Gate Drives for High Efficiency
  • DCM Operation at Light Loads
  • Auxiliary Bootstrap LDO
• Operates Reliably in Adverse Industrial Environments
  • Programmable Soft-Stop Enable or Disable Function
  • Adjustable Soft-Start
  • Current Foldback Limits MOSFET Heat Dissipation During a Short-Circuit Condition
  • Overtemperature Protection
  • High Industrial Ambient Operating Temperature Range (-40°C to +125°C) and Junction Tempera- ture Range (-40°C to +150°C)

The MAX17557 is a synchronous step-down controller that drives nMOSFETs. The device uses a constant-frequency, peak-current-mode architecture.

The IC supports current sensing using either an external current-sense resistor for accuracy or an inductor DCR for improved system efficiency. Current foldback limits MOSFET power dissipation under short-circuit conditions.

The IC can start up monotonically into a prebiased output. The device can be operated in forced pulse-width modulation (PWM), or discontinuous-conduction mode (DCM) to enable high efficiency under full-load and light-load conditions. The device features a programmable soft-stop enable (SSTPEN) or disable function.

The IC operates over the -40°C to +125°C temperature range and is available in a lead (Pb)-free, 20-pin TQFN, 4mm x 4mm package with an exposed pad.

Applications

• Computerized Numerical Control
• Distributed DC Power Systems
• Industrial Power Supplies
• Motion Control
• Programmable Logic Controllers