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.