深圳市中立信电子科技有限公司

1 Features 3 Description

The LM2831 regulator is a monolithic, high1•

Space-Saving SOT-23 Package

frequency, PWM step-down DC-DC converter in a 5-

• Input Voltage Range of 3 V to 5.5 V pin SOT-23 and a 6-Pin WSON package. The

• Output Voltage Range of 0.6 V to 4.5 V LM2831 provides all the active functions to provide

• 1.5-A Output Current local DC-DC conversion with fast transient response

and accurate regulation in the smallest possible PCB • High Switching Frequencie

area. With a minimum of external components, the

– 1.6 MHz (LM2831X) LM2831 is easy to use. The ability to drive 1.5-A

– 0.55 MHz (LM2831Y) loads with an internal 130-mΩ PMOS switch using

state-of-the-art 0.5-μm BiCMOS technology results in – 3 MHz (LM2831Z) the best power density available. The world-class

• 130-mΩ PMOS Switch control circuitry allows on-times as low as 30 ns, thus

• 0.6-V, 2% Internal Voltage Reference supporting exceptionally high frequency conversion

over the entire 3 V to 5.5 V input operating range, • Internal Soft Start

down to the minimum output voltage of 0.6 V.

• Current Mode, PWM Operation Switching frequency is internally set to 550 kHz, 1.6

• Thermal Shutdown MHz, or 3 MHz, allowing the use of extremely small

• Overvoltage Protection surface mount inductors and chip capacitors. Even

though the operating frequency is high, efficiencies of

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

included, featuring an ultra-low standby current of 30

• Local 5 V to Vcore Step-Down Converters nA. The LM2831 utilizes current-mode control and

• Core Power in HDDs internal compensation to provide high-performance

regulation over a wide range of operating conditions. • Set-Top Boxes

Additional features include internal soft-start circuitry

• USB Powered Devices to reduce inrush current, pulse-by-pulse current limit,

• DSL Modems thermal shutdown, and output overvoltage protection.