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LM2651

SNVS032E – FEBRUARY 2000 – REVISED JANUARY 2016

LM2651 1.5 A High-Efficiency Synchronous Switching Regulator

1 Features

3 Description

The LM2651 switching regulator provides high-

1

•

Ultrahigh Efficiency up to 97%

efficiency power conversion over a 100:1 load range

•

High-Efficiency Over a 1.5-A to 1.5-mA Load

(1.5 A to 15 mA). This feature makes the LM2651 an

Range

ideal fit in battery-powered applications that demand

•

4-V to 14-V Input Voltage Range

long battery life in both run and standby modes.

•

1.8-V, 2.5-V, 3.3-V, or ADJ Output Voltage

Synchronous rectification is used to achieve up to

•

97% efficiency. At light loads, the LM2651 enters a

low power hysteretic or sleep mode to maintain high

75 m

Ω

efficiency. In many applications, the efficiency still

•

300-kHz Fixed Frequency Internal Oscillator

exceeds 80% at 15-mA load. A shutdown pin is

•

7-µA Shutdown Current

available to disable the LM2651 and reduce the

•

Patented Current Sensing for Current Mode

supply current to less than 10 µA.

Control

The LM2651 contains a patented current sensing

•

Input Undervoltage Lockout

circuitry for current mode control. This feature

eliminates

the

external

current

sensing

resistor

•

Adjustable Soft-Start

required by other current-mode DC-DC converters.

•

Current Limit and Thermal Shutdown

The LM2651 has a 300-kHz fixed frequency internal

•

16-Pin TSSOP Package

oscillator. The high oscillator frequency allows the

use of extremely small, low-profile components.

2 Applications

A programmable soft-start feature limits current

•

Personal Digital Assistants (PDAs)

surges from the input power supply at start-up and

•

Computer Peripherals

provides a simple means of sequencing multiple

•

Battery-Powered Devices

power supplies.

•

Handheld Scanners

Other protection features include input undervoltage

•

High-Efficiency 5-V Conversion

lockout, current limiting, and thermal shutdown.

Device Information(1)

PART NUMBER

PACKAGE

BODY SIZE (NOM)

LM2651

TSSOP (16)

5.00 mm × 4.40 mm

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

the end of the data sheet.

Typical Application

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.