Features

• Complete 20A Switch Mode Power Supply
• 4.5V to 20V Input Voltage Range
• 0.6V to 5.5V Output Voltage Range
• ±1.5% Total DC Output Voltage Error (–40°C to 125°C)
• Differential Remote Sense Amplifier for Precision Regulation for (V_OUT ≤ 3.3V)
• Current Mode Control/Fast Transient Response
• Parallel Current Sharing (Up to 80A)
• Frequency Synchronization
• Selectable Pulse-Skipping or Burst Mode® Operation
• Soft-Start/Voltage Tracking
• Up to 88% Efficiency (12V_IN, 1.8V_OUT)
• Overcurrent Foldback Protection
• Output Overvoltage Protection
• Internal Temperature Monitor
• Overtemperature Protection
• 15mm × 15mm × 4.32mm LGA and
  15mm × 15mm × 4.92mm BGA Packages
• SnPb (BGA) or RoHS Compliant (LGA and BGA) Finish

Typical Application

Description

The LTM®4637 is a complete 20A output high efficiency switch mode step-down DC/DC μModule (power module) regulator. Included in the package are the switching controller, power FETs, inductor and compensation components. Operating over an input voltage range from 4.5V to 20V, the LTM4637 supports an output voltage range of 0.6V to 5.5V, set by a single external resistor. Only a few input and output capacitors are needed.

Current mode operation allows precision current sharing of up to four LTM4637 regulators to obtain up to 80A output. High switching frequency and a current mode architecture enable a very fast transient response to line and load changes without sacrificing stability. The device supports frequency synchronization, multiphase/current sharing, Burst Mode operation and output voltage tracking for supply rail sequencing. A diode-connected PNP transistor is available for use as an internal temperature monitor.

The LTM4637 is offered in 15mm × 15mm × 4.32mm LGA and 15mm × 15mm × 4.92mm packages. The LTM4637 is available with SnPb (BGA) or RoHS compliant terminal finish. The LTM4637 is pin compatible with the LTM4627, a 15A DC/DC μModule regulator.