Features

• Complete 20A Switch Mode Power Supply
• 2.375V to 7V Input Voltage Range (V_IN < 4.5V, Need CPWR Bias)
• 0.6V to 5.5V Output Voltage Range
• ±1.5% Maximum Total DC Output Voltage Error (–40°C to 125°C)
• Differential Remote Sense Amplifier for Precision Regulation (V_OUT ≤ 3.3V)
• Current Mode Control/Fast Transient Response
• Parallel Multiphase Current Sharing (Up to 80A)
• Frequency Synchronization
• Selectable Pulse-Skipping or Burst Mode® Operation
• Soft-Start/Voltage Tracking
• Up to 88% Efficiency (3.3V_IN, 1.5V_OUT)
• Overcurrent Foldback Protection
• Output Overvoltage Protection
• Internal Temperature Monitor
• Overtemperature Protection
• 15mm × 15mm × 4.92mm BGA Package

Typical Application

Description

The LTM®4639 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 2.375V to 7V, the LTM4639 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 LTM4639 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 included for use as an internal temperature monitor. For up to 20V input operation, please see the LTM4637.

The LTM4639 is offered in a 15mm × 15mm × 4.92mm BGA package. The LTM4639 is RoHS compliant.