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dc2681aaf
DEMO MANUAL DC2681A-A
DESCRIPTION
LTM4645
25A DC/DC Step-Down
µModule Regulator
Demonstration circuit DC2681A-A features the
LTM
®
4645EY, a 25A high efficiency, switch mode step-
down power µModule
®
regulator. The input voltage
range is from 6V to 15V. To use DC2681A-A for input
voltage range from 4.7V to 6V, connect INTV
CC
to SV
IN
(change R22 from OPT to 0Ω), DRV
CC
to V
IN
(change
R21 from 0Ω to OPT, R28 from OPT to 0Ω). The output
voltage range is 0.6V to 1.8V. Derating is necessary for
certain V
IN
, V
OUT
, frequency and thermal conditions. The
DC2681A-A offers the TRK/SS pin allowing the user to
program output tracking or soft-start period. The board
operates in continuous conduction mode in heavy load
conditions. For high efficiency at low load currents, the
MODE_PLLIN jumper selects pulse-skipping mode for
noise sensitive applications or burst mode operation in
L
, LT, LTC, LTM, µModule, Linear Technology and the Linear logo are registered trademarks of
Analog Devices, Inc. All other trademarks are the property of their respective owners.
BOARD PHOTO
less noise sensitive applications. The MODE_PLLIN pin
also allows the
LTM4645
to synchronize to an external
clock signal (between 400kHz and 800kHz). DC2681A-A
has the option of choosing both internal and external
compensation circuit for LTM4645. Tying the PHASMD
pin to different voltage generates certain phase differ-
ence between MODE_PLLIN and CLKOUT. The LTM4645
data sheet must be read in conjunction with this demo
manual prior to working on or modifying demo circuit
DC2681A-A.
Design files for this circuit board are available at
http://www.linear.com/demo/DC2681A-A
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