1 Features

1• Compliant with CISPR25 Class 5 Conducted

Emissions

• Input Voltage Range of 3 V to 5.5 V

• Output Voltage Range of 0.8 V to 4.5 V

• 2-A Output Current per Regulator

• High Switching Frequency: 2.2 MHz (LM26420X)

0.55 MHz (LM26420Y)

• 0.8 V, 1.5% Internal Voltage Reference

• Internal Soft Start

• Independent Power Good and Precision Enable

for Each Output

• Current Mode, PWM Operation

• Thermal Shutdown

• Overvoltage Protection

• Start-up into Prebiased Output Loads

• Regulators are 180° Out of Phase

• Create a Custom Design Using the LM26420 With

the WEBENCH® Power Designer

2 Applications

• Local 5 V to Vcore of FPGAs

• Core Power in HDDs and Set-Top Boxes

• USB Powered Devices

• Powering Core and I/O Voltages for CPUs and

ASICs

3 Description

The LM26420 regulator is a monolithic, highefficiency

dual PWM step-down DC/DC converter.

This device has the ability to drive two 2-A loads with

an internal 75-mΩ PMOS top switch and an internal

50-mΩ NMOS bottom switch using state-of-the-art

BICMOS technology results in the best power density

available. The world-class control circuitry allow on

times as low as 30 ns, thus supporting exceptionally

high-frequency conversion over the entire 3-V to 5.5-

V input operating range down to the minimum output

voltage of 0.8 V.

Although the operating frequency is high, efficiencies

up to 93% are easy to achieve. External shutdown is

included, featuring an ultra-low standby current. The

LM26420 utilizes current-mode control and internal

compensation to provide high performance regulation

over a wide range of operating conditions.