LM2705_07 Datasheet, PDF (1/12 Pages) National Semiconductor (TI) – Micropower Step-up DC/DC Converter with 150mA Peak Current Limit

August 2007
LM2705
Micropower Step-up DC/DC Converter with 150mA Peak
Current Limit
General Description
The LM2705 is a micropower step-up DC/DC in a small 5-lead
SOT-23 package. A current limited, fixed off-time control
scheme conserves operating current resulting in high effi-
ciency over a wide range of load conditions. The 21V switch
allows for output voltages as high as 20V. The low 400ns off-
time permits the use of tiny, low profile inductors and capac-
itors to minimize footprint and cost in space-conscious
portable applications. The LM2705 is ideal for LCD panels
requiring low current and high efficiency as well as white LED
applications for cellular phone back-lighting. The LM2705 can
drive up to 3 white LEDs from a single Li-Ion battery. The low
peak inductor current of the LM2705 makes it ideal for USB
applications.
Features
■ ^{150mA, 0.7Ω, internal switch}
■ ^{Uses small surface mount components}
■ ^{Adjustable output voltage up to 20V}
■ ^{2.2V to 7V input range}
■ ^{Input undervoltage lockout}
■ ^{0.01µA shutdown current}
■ ^{Small 5-Lead SOT-23 package}
Applications
■ ^{LCD Bias Supplies}
■ ^{White LED Back-Lighting}
■ ^{Handheld Devices}
■ ^{Digital Cameras}
■ ^{Portable Applications}
Typical Application Circuit
FIGURE 1. Typical 20V Application
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