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dc1543afa
DEMO MANUAL DC1543A
DESCRIPTION
LTM4641
38V, 10A, Step-Down µModule Regulator
with Advanced Input and Load Protection
Demonstration circuit 1543A features the LTM
®
4641, a
high efficiency, high density switch mode step-down power
μModule regulator with superior input and load protection
features. The input voltage range is from 4.5V to 38V. The
output voltage is jumper programmable from 0.8V to 6V
with a rated load current of 10A. Derating is necessary
for certain V
IN
, V
OUT
, frequency and thermal conditions.
DC1543A offers the TRACK/SS pin allowing the user to
program output tracking or soft-start period. The DC1543A
allows the user to enable/disable input undervoltage
L
, LT, LTC, LTM, μModule, Linear Technology and the Linear logo are registered trademarks of
Linear Technology Corporation. All other trademarks are the property of their respective owners.
PERFORMANCE SUMMARY
BOARD PHOTO
protection; input latching/non-latching overvoltage protec-
tion; and latching/non-latching overtemperature protection.
Higher efficiency at low load currents is achieved by setting
the MODE pin jumper to DCM. The LTM4641 data sheet
must be read in conjunction with this demo manual prior
to working on or modifying demo circuit 1543A.
Design files for this circuit board are available at
http://www.linear.com/demo
PARAMETER
CONDITIONS
VALUE
Input Voltage Range
4.5V to 38V
Output Voltage V
OUT
Jumper Selectable
0.8V, 1.0V, 1.2V, 1.5V, 1.8V, 3.3V, 5V, 6V; ±1.5%
Maximum Continuous Output Current
Derating is Necessary for Certain Operating Conditions.
See Data Sheet for Details.
10A
DC
Default Operating Frequency
R
fSET
= 680kΩ for V
OUT
= 0.8V, 1.0V, 1.2V, 1.5V, 1.8V;
R
fSET
= ∞ (Not Stuffed) for V
OUT
= 3.3V, 5.0V, 6.0V
255kHz (V
OUT
= 0.8V); 320kHz (V
OUT
= 1.0V);
385kHz (V
OUT
= 1.2V); 480kHz (V
OUT
= 1.5V);
575kHz (V
OUT
= 1.8V); 360kHz (V
OUT
= 3.3V);
550kHz (V
OUT
= 5.0V); 660kHz (V
OUT
= 6.0V);
Efficiency
V
IN
= 12V, V
OUT
= 6V, I
OUT
= 10A
93.0% See Figure 2
Load Transient
V
IN
= 12V, V
OUT
= 3.3V
See Figure 3
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