LM2705 Datasheet, PDF (1/11 Pages) National Semiconductor (TI) – Micropower Step-up DC/DC Converter with 150mA Peak Current Limit

April 2003
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
efficiency 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 capacitors 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
n 150mA, 0.7Ω, internal switch
n Uses small surface mount components
n Adjustable output voltage up to 20V
n 2.2V to 7V input range
n Input undervoltage lockout
n 0.01µA shutdown current
n Small 5-Lead SOT-23 package
Applications
n LCD Bias Supplies
n White LED Back-Lighting
n Handheld Devices
n Digital Cameras
n Portable Applications
Typical Application Circuit
FIGURE 1. Typical 20V Application
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