LM2623 General-Purpose, Gated-Oscillator-Based DC-DC Boost Converter

1 Features

• 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 V_DD 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 battery-powered 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.

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

Typical Application Circuit

4 Revision History

Changes from H Revision (November 2014) to I Revision

• Changed Handling Ratings table to ESD Ratings to comply with current formatGo
• Moved Storage temperature spec to Abs Max table Go
• Added separate row for SW pin HBM ESD rating Go
• Added condition to Recommended Operating Conditions table Go
• Changed Updated R_θJA value for NHE package from "40 – 56" to "46.5"°C/W and DGK package from "240" to 152.5" °C/W; added additional thermal informationGo

Changes from G Revision (December 2005) to H Revision

• Added Device Information and Handling Rating tables, Feature Description, Device Functional Modes, Application and Implementation, Power Supply Recommendations, Layout, Device and Documentation Support, and Mechanical, Packaging, and Orderable Information sections; moved some curves to Application Curves sectionGo

5 Pin Configuration And Functions

NHE Package

14-Pin WSON

Top View

DGK Package

8-Pin VSSOP

Top View