1 Features

• 24-μA Quiescent Current in Regulation

• High Efficiency at Light Load (DCM and PFM)

• Meets EN55022/CISPR 22 EMI standards

• Integrated Synchronous Rectification

• Adjustable Frequency Range: 200 kHz to 2.2 MHz

(500 kHz default)

• Frequency Synchronization to External Clock

• Internal Compensation

• Stable With Almost Any Combination of Ceramic,

Polymer, Tantalum, and Aluminum Capacitors

• Power-Good Flag

• Soft-Start into Prebiased Load

• Internal Soft Start: 4.1 ms

• Extendable Soft-Start Time by External Capacitor

• Output Voltage Tracking Capability

• Precision Enable to Program System UVLO

• Output Short-Circuit Protection With Hiccup Mode

• Overtemperature Thermal Shutdown Protection

• Create a Custom Design Using the LM46000 With

the WEBENCH® Power Designer

2 Applications

• Industrial Power Supplies

• Telecommunications Systems

• Sub-AM Band 12-V and 24-V Automotive

• Commercial Vehicle Power Supplies

• General Purpose Wide VIN Regulation

• High Efficiency Point-Of-Load Regulation

3 Description

The LM46000 regulator is an easy-to-use

synchronous step-down DC-DC converter capable of

driving up to 500 mA of load current from an input

voltage range of 3.5 V to 60 V. The LM46000

provides exceptional efficiency, output accuracy and

dropout voltage in a very small solution size. An

extended family is available in 1 A and 2 A load

current options in pin-to-pin compatible packages.

Peak current mode control is employed to achieve

simple control loop compensation and cycle-by-cycle

current limiting. Optional features such as

programmable switching frequency, synchronization,

power-good flag, precision enable, internal soft start,

extendable soft start, and tracking provide a flexible

and easy-to-use platform for a wide range of

applications. Discontinuous conduction and automatic

frequency modulation at light loads improve light load

efficiency. The family requires few external

components and pin arrangement allows simple,

optimum PCB layout. Protection features include

thermal shutdown, VCC undervoltage lockout, cycleby-

cycle current limit, and output short-circuit

protection. The LM46000 device is available in the

16-pin leaded HTSSOP (PWP) package (6.6 mm ×

5.1 mm × 1.2 mm) with 0.65-mm lead pitch. Pin-topin

compatible with LM46001, LM46002, LM43603,

LM43602, LM43601, and LM43600.