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dc1453af
DEMO MANUAL DC1453A
DESCRIPTION
LTM4619EV: 4.5V-28V,
Dual 4A Step-Down µModule
Regulator
Demonstration circuit 1453A features the LTM
®
4619EV, the
high input voltage, high effi ciency, high density, dual 4A
step-down power module. Derating is necessary for certain
V
IN
, V
OUT
, and thermal conditions. The two outputs are
interleaved with 180° phase to minimize the input ripple
and reduce the input capacitors. A minimum design only
requires the bulk input and output capacitors and voltage
setting resistors. The LTM4619EV features output voltage
tracking, power good indicator, RUN pin control, clock
synchronization and soft-start programming. Protection
L
, LT, LTC, LTM, Linear Technology, the Linear logo, μModule and Burst Mode are registered
trademarks of Linear Technology Corporation. All other trademarks are the property of their
respective owners.
BOARD PHOTO
PERFORMANCE SUMMARY
(T
A
= 25°C)
features include foldback current limiting and overvolt-
age protection. Burst Mode
®
operation or pulse skipping
mode can be selected for better light load effi ciency. The
LTM4619 data sheet must be read in conjunction with
this demo manual for working on or modifying the demo
circuit 1453A.
Design fi les for this circuit board are available at
http://www.linear.com/demo
PARAMETER
CONDITION
VALUE
Input Voltage Range
4.5V to 28V
Output Voltage V
OUT1
, V
OUT2
3.3V ±2%, 1.8V ±2%
Maximum Continuous Output Current
Derating Is Necessary for Certain V
IN
, V
OUT
, and Thermal Conditions,
See Datasheet for Details.
4A
DC
for V
OUT1
, V
OUT2
Default Operating Frequency
JP2 on the 500kHz position.
500kHz
Effi ciency of Channel 1
V
IN
= 12V, V
OUT1
= 3.3V, I
OUT1
= 4A, Switching Frequency = 500kHz.
89.4%, See Figure 3
Effi ciency of Channel 2
V
IN
= 12V, V
OUT2
= 1.8V, I
OUT2
= 4A, Switching Frequency = 500kHz.
84.1% See Figure 3