1 Features

1• High-Efficiency Synchronous DC/DC Converter

– Input Voltage Range of 2.95 V to 5.5 V

– Adjustable Output Voltage From 0.6 V to VIN

– Output Current as High as 15 A

• Frequency Synchronization 300 kHz to 1.5 MHz

• Integrated 7-mΩ PMOS Buck Switch Supports

100% Duty Cycle for Low Dropout Voltage

• Integrated 4.3-mΩ NMOS Synchronous Rectifier

Eliminates Schottky Diode

• Accurate ±1% Internal Voltage Reference

• Automatic Diode Emulation Mode for Improved

Efficiency at Light Loads

• Monotonic Pre-Biased Startup

• Internal 0.5-ms or Externally Adjustable Soft Start

• Output Voltage Tracking Capability

• Ultra-Fast Line and Load Transient Response

– Voltage-Mode PWM Control

– Wide-Bandwidth Voltage Loop Error Amplifier

• Precision Enable with Hysteresis

• Integrated OVP, UVP, OCP, and UVLO

• Open-Drain Power Good Indicator

• Thermal Shutdown Protection With Hysteresis

• Thermally-Enhanced HTSSOP-20 Package

• Create a custom design using the LM21215A with

the WEBENCH® Power Designer

2 Applications

• Telecommunications Infrastructure

• DSP and FPGA Core Voltage Supplies

• High Efficiency POL Conversion

• Embedded Computing, Servers and Storage

3 Description

The LM21215A is a synchronous buck DC-DC

converter that delivers up to 15 A of output current at

output voltages as low as 0.6 V. Operating over an

input voltage range of 2.95 V to 5.5 V with ultra-high

efficiency, the LM21215A suits a wide variety of low

voltage systems. The voltage-mode control loop with

high gain-bandwidth error amplifier provides high

noise immunity, narrow duty cycle capability and is

easily compensated for stable operation with any type

of output capacitor, providing maximum flexibility and

ease of use.

The LM21215A features internal overvoltage

protection (OVP) and cycle-by-cycle overcurrent

protection (OCP) for increased system reliability. A

precision enable pin and integrated UVLO allow turnon

of the device to be tightly controlled and

sequenced. Startup inrush currents are limited by an

internally-fixed or externally-adjustable soft-start

circuit. An integrated open-drain PGOOD indicator

provides fault reporting and supply sequencing.

Other features include auxiliary voltage rail tracking,

monotonic startup into pre-biased loads, and

switching frequency synchronization to an external

clock signal between 300 kHz and 1.5 MHz for beatfrequency

sensitive and multi-regulator applications.

The LM21215A is offered in a thermally-enhanced

20-pin HTSSOP package with an exposed pad that is

soldered to the PCB to achieve a very low junction-toboard

thermal impedance.