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.