LM2705 Micropower Step-up DC/DC Converter with 150mA Peak Current Limit
April 2003
LM2705 Micropower Step-up DC/DC Con...
LM2705 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 spaceconscious 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 n n n n n n 150mA, 0.7Ω, internal switch Uses small surface mount components Adjustable output
voltage up to 20V 2.2V to 7V input range Input under
voltage lockout 0.01µA shutdown current Small 5-Lead SOT-23 package
Applications
n n n n n LCD Bias Supplies White LED Back-Lighting Handheld Devices Digital Cameras Portable Applications
Typical Application Circuit
20039701
FIGURE 1. Typical 20V Application
© 2003 National Semiconductor Corporation
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LM2705
Connection Diagram
Top View
20039702
TJmax
SOT23-5 = 125˚C, θJA = 220˚C/W (Note 2)
Orde...