LM2698 Datasheet, PDF (1/17 Pages) National Semiconductor (TI) – SIMPLE SWITCHER 1.35A Boost Regulator

October 2001
LM2698
SIMPLE SWITCHER^® 1.35A Boost Regulator
General Description
The LM2698 is a general purpose PWM boost converter.
The 1.9A, 18V, 0.2ohm internal switch enables the LM2698
to provide efficient power conversion to outputs ranging from
2.2V to 17V. It can operate with input voltages as low as 2.2V
and as high as 12V. Current-mode architecture provides
superior line and load regulation and simple frequency com-
pensation over the device’s 2.2V to 12V input voltage range.
The LM2698 sets the standard in power density and is
capable of supplying 12V at 400mA from a 5V input. The
LM2698 can also be used in flyback or SEPIC topologies.
The LM2698 SIMPLE SWITCHER^® features a pin selectable
switching frequency of either 600kHz or 1.25MHz. This pro-
motes flexibility in component selection and filtering tech-
niques. A shutdown pin is available to suspend the device
and decrease the quiescent current to 5µA. An external
compensation pin gives the user flexibility in setting fre-
quency compensation, which makes possible the use of
small, low ESR ceramic capacitors at the output. Switchers
Made Simple^® software is available to insure a quick, easy
and guaranteed design. The LM2698 is available in a low
profile 8-lead MSOP package.
Features
n 1.9A, 0.2Ω, internal switch (typical)
n Operating voltage as low as 2.2V
n 600kHz/1.25MHz adjustable frequency operation
n Switchers Made Simple^® software
n 8-Lead MSOP package
Applications
n 3.3V to 5V, 5V to 12V conversion
n Distributed Power
n Set-Top Boxes
n DSL Modems
n Diagnostic Medical Instrumentation
n Boost Converters
n Flyback Converters
n SEPIC Converters
Typical Application Circuit
SIMPLE SWITCHER^® is a registered trademark of National Semiconductor Corporation.
© 2001 National Semiconductor Corporation DS200126
20012658
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