LTM4645
25A DC/DC Step-Down
µModule Regulator
FeaTures
DescripTion
TheLTM®4645isa25Aoutputswitchingmodestep-down
DC/DC µModule® (power module) regulator. Included in
the package are the switching controller, power FETs, in-
ductor and all supporting components. Operating over an
input voltage range of 4.7V to 15V, the LTM4645 supports
an output voltage range of 0.6V to 1.8V, set by a single
external resistor. Only a few input and output capacitors
are needed.
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4.7V to 15V Input Voltage Range
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0.6V to 1.8V Output Voltage Range
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25A DC Output Current
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1.2ꢀTotalDCOutputVoltageError(–40°Cto125°C)
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HighReliabilityN+1PhaseRedundancySupported
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InternalorExternalControlLoopCompensation
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Differential Remote Sense Amplifier for Precision
Regulation
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Current Mode Control/Fast Transient Response
Its high efficiency design delivers about 86% efficiency
from 12V input to 1.0V output with 25A continuous load
current. High switching frequency and a current-mode
architecture enable a very fast transient response to line
and load changes without sacrificing stability. The device
supports frequency synchronization, programmable
multiphase operation, N+1 phase redundancy, and output
voltage tracking for supply rail sequencing.
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Multiphase Current Sharing Up to 150A
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Built-In Temperature Monitoring
Selectable Pulse-Skipping, Burst Mode® Operation
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Soft-Start/Voltage Tracking
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Frequency Synchronization
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Output Overvoltage Protection
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Output Overcurrent Foldback Protection
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9mm × 15mm × 3.51mm BGA Package
Fault protection features include overvoltage and overcur-
rent protection. The power module is offered in a space
saving 9mm × 15mm × 3.51mm BGA package. The
LTM4645 is available with SnPb (BGA) or RoHS compli-
ant terminal finish.
applicaTions
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Telecom, Networking and Industrial Equipment
Point of Load Regulation
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L, LT, LTC, LTM, Linear Technology, the Linear logo, Burst Mode, µModule, LTpowerCAD
and PolyPhase are registered trademarks of Analog Devices, Inc. All other trademarks are the
property of their respective owners.
Typical applicaTion
Efficiency vs Output Current
at 1V Output
12VIN, 1VOUT, 25A DC/DC µModule Regulator
100
95
4.7µF
1µF
6.3V
2.2Ω
SV
DRV
INTV
90
85
IN
CC
CC
V
IN
V
IN
6V TO 15V
22µF
25V
×2
HIZB
FREQ
LTM4645
80
75
70
65
60
V
OUT
1V
V
OUT
+
25A
43.2k
V
V
47pF
COMPa
COMPb
OSNS
V
FB
–
100µF
6.3V
×4
TRACK/SS
OSNS
90.9k
5V INPUT
12V INPUT
0.1µF
SGND GND
4645 TA01a
10
15
20
25
0
5
PINS NOT USED IN THIS CIRCUIT:
LOAD CURRENT (A)
CLKOUT, MODE/PLLIN, PGOOD,
+
–
4645 TA01b
PHASMD, PWM, RUN, SW, TEMP , TEMP
4645f
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For more information www.linear.com/LTM4645