1 Features

1• Good Efficiency Over a Very Wide Load Range

• Very Low Output Voltage Ripple

• Up to 2-MHz Switching Frequency

• 0.8-V to 14-V Operating Voltage

• 1.1-V Start-up Voltage

• 1.24-V to 14-V Adjustable Output Voltage

• Up to 2-A Load Current at Low Output Voltages

• 0.17-Ω Internal MOSFET

• Up to 90% Regulator Efficiency

• 80-μA Typical Operating Current (Into VDD Pin of

Supply)

• < 2.5-μA Ensured Supply Current In Shutdown

• Small 8-Pin VSSOP Package (Half the Footprint

of Standard 8-Pin SOIC Package); 1.09-mm

Package Height

• 4-mm × 4-mm Thermally Enhanced WSON

Package Option

2 Applications

• Cameras, Pagers and Cell Phones

• PDAs, Palmtop Computers, GPS devices

• White LED Drive, TFT, or Scanned LCDs

• Flash Memory Programming

• Hand-Held Instruments

• 1, 2, 3, or 4 Cell Alkaline Systems

• 1, 2, or 3 Cell Lithium-ion Systems

3 Description

The LM2623 is a high-efficiency, general-purpose,

step-up DC-DC switching regulator for batterypowered

and low input voltage systems. It accepts an

input voltage between 0.8 V and 14 V and converts it

into a regulated output voltage between 1.24 V and

14 V. Efficiencies up to 90% are achievable with the

LM2623.

In order to adapt to a number of applications, the

LM2623 allows the designer to vary the output

voltage, the operating frequency (300 kHz to 2 MHz)

and duty cycle (17% to 90%) to optimize the part's

performance. The selected values can be fixed or can

vary with battery voltage or input to output voltage

ratio. The LM2623 uses a very simple, on/off

regulation mode to produce good efficiency and

stable operation over a wide operating range. It

normally regulates by skipping switching cycles when

it reaches the regulation limit (Pulse Frequency

Modulation).

Note: See Non-Linear Effect and Choosing The

Correct C3 Capacitor so that any challenges with

designing with this part can be taken into account

before a board design/layout is finalized.

For alternative solutions, See Also: LM2700, LM2622,

LM2731, LM2733, and LM2621.