1 Features

• Input Voltage Range of 3 V to 20 V
• Dual 2-A Output
• Output Voltage Down to 0.6 V
• Internal Compensation
• 500-kHz PWM Frequency
• Separate Enable Pins
• Separate Soft-Start Pins
• Frequency Foldback Protection
• 175-mΩ NMOS Switch
• Integrated Bootstrap Diodes
• Overcurrent Protection
• HTSSOP and WSON Packages
• Thermal Shutdown

2 Applications

• DTV-LCD
• Set-Top Boxes
• XDSL
• Automotive
• Computing Peripherals
• Industrial Controls
• Points-of-Load

3 Description

The LM26400Y device is a monolithic, two-output fixed-frequency PWM step-down DC-DC regulator, in a 16-pin WSON or thermally-enhanced HTSSOP package. With a minimum number of external components and internal loop compensation, the LM26400Y is easy to use.

The ability to drive 2-A loads with an internal 175-mΩ NMOS switch using state-of-the-art 0.5-µm BiCMOS technology results in a high-power density design. The world class control circuitry allows for an ON-time as low as 40 ns, thus supporting high-frequency conversion over the entire input range of 3 V to 20 V and down to an output voltage of only 0.6 V. The LM26400Y utilizes peak current-mode control and internal compensation to provide high-performance regulation over a wide range of line and load conditions. Switching frequency is internally set to 500 kHz, optimal for a broad range of applications in terms of size versus thermal tradeoffs.

Given a nonsynchronous architecture, efficiencies above 90% are easy to achieve. External shutdown is included, enabling separate turnon and turnoff of the two channels. Additional features include programmable soft-start circuitry to reduce inrush current, pulse-by-pulse current limit and frequency foldback, integrated bootstrap structure, and thermal shutdown.

1. For all available packages, see the orderable addendum at the end of the data sheet.

Typical Application