LM2738YMY/NOPB

The LM2738 regulator is a monolithic, highfrequency, PWM step-down DC-DC converter in an 8-pin WSON or 8-pin MSOP-PowerPAD package. It provides all the active functions for local DC-DC conversion with fast transient response and accurate regulation in the smallest possible PCB area. With a minimum of external components, the LM2738 is easy to use. The ability to drive 1.5-A loads with an internal 250 mΩ NMOS switch using state-of-the-art 0.5-μm BiCMOS technology results in the best power density available. Switching frequency is internally set to 550 kHz (LM2738Y) or 1.6 MHz (LM2738X), allowing the use of extremely small surface-mount inductors and chip capacitors. Even though the operating frequencies are very high, efficiencies up to 90% are easy to achieve. External enable is included, featuring an ultralow standby current of 400 nA. The LM2738 utilizes current-mode control and internal compensation to provide high-performance regulation over a wide range of operating conditions. Additional features include internal soft-start circuitry to reduce in-rush current, cycle-by-cycle current limit, thermal shutdown, and output over-voltage protection.

Applications

• Local Point of Load Regulation
• Core Power in HDDs
• Set-Top Boxes
• Battery Powered Devices
• USB Powered Devices
• DSL Modems

Key features

• Space-Saving WSON and MSOP-PowerPAD Packages
• 3-V to 20-V Input Voltage Range
• 0.8-V to 18-V Output Voltage Range
• 1.5-A Output Current
• 550-kHz (LM2738Y) and 1.6-MHz (LM2738X) Switching Frequencies
• 250 mΩ NMOS Switch
• 400-nA Shutdown Current
• 0.8-V, 2% Internal Voltage Reference
• Internal Soft-Start
• Current-Mode, PWM Operation
• Thermal Shutdown