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LM27402

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VDD

GND

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Design

LM27402

SNVS615J – JANUARY 2010 – REVISED JULY 2015

LM27402 High-Performance Synchronous Buck Controller With DCR Current Sensing

1 Features

3 Description

The LM27402 is a voltage-mode, synchronous, DC-

1

•

Wide Input Voltage Range of 3 V to 20 V

DC step-down controller with lossless inductor DCR

•

Inductor DCR or Shunt Resistor Based

current sensing capability. Sensing the inductor

Overcurrent Protection

current

eliminates

the

need

to

add

resistive

•

0.6-V Reference With ±1% FB Accuracy Across

powertrain

elements,

which

increases

overall

efficiency and facilitates accurate, continuous current

Full –40°C to 125°C Junction Temperature Range

sensing. A 0.6-V ±1% voltage reference enables high

•

Switching Frequency from 200 kHz to 1.2 MHz

accuracy and low voltage capability at the output. An

•

Output Voltage as High as 95% of Input Voltage

input operating voltage range of 3 V to 20 V makes

•

Integrated High-Current MOSFET Drivers

the LM27402 suitable for a large variety of input rails.

•

Internal VDD Bias Supply LDO Subregulator

The LM27402 voltage-mode control loop incorporates

•

External Clock Synchronization

input

voltage

feed-forward

to

maintain

stability

throughout the entire input voltage range. The

•

Adjustable Soft-Start With External Capacitor

switching frequency is adjustable from 200 kHz to

•

Pre-Biased Start-up Capability

1.2 MHz. Dual, high-current, integrated MOSFET

•

Power Supply Tracking

drivers

support

large

low

power

MOSFETs. A power good indicator provides power

•

Voltage-Mode Control With Line Feedforward

rail sequencing capability and output fault detection.

•

Open-Drain Power Good Indicator

An adjustable external soft-start limits inrush current

•

Precision Enable With Hysteresis

and provides monotonic output control during start-

•

HTSSOP-16 and WQFN-16 Packages

up. Other features include external tracking of other

power supplies, integrated LDO bias supply, and

synchronization capability.

2 Applications

•

High Current, Low Voltage Supply for FPGA and

Device Information(1)

ASIC

PART NUMBER

PACKAGE

BODY SIZE (NOM)

•

General-Purpose, High-Current Buck Converters

WQFN (16)

4.00 mm × 4.00 mm

LM27402

•

DC-DC Converters and POL Modules

HTSSOP (16)

5.00 mm × 4.40 mm

•

Telecom, Datacom, Networking, Distributed Power

(1) For all available packages, see the orderable addendum at

Architectures

the end of the data sheet.

Typical Application Circuit

1

An IMPORTANT NOTICE at the end of this data sheet addresses availability, warranty, changes, use in safety-critical applications,

intellectual property matters and other important disclaimers. PRODUCTION DATA.