LTM4605 Datasheet, PDF (1/24 Pages) Linear Technology – High Effi ciency Buck-Boost DC/DC μModule

LTM4605
High Efficiency
Buck-Boost DC/DC µModule
FEATURES
n _{Single Inductor Architecture Allows VIN Above,}
Below or Equal to V_OUT
n _{Wide VIN Range: 4.5V to 20V}
n _{Wide VOUT Range: 0.8V to 16V}
n _{5A DC Typical (12A DC Typical at Buck Mode)}
n _{High Efficiency Up to 98%}
n _{Current Mode Control}
n _{Power Good Output Signal}
n _{Phase-Lockable Fixed Frequency: 200kHz to 400kHz}
n _{Ultra-Fast Transient Response}
n _{Current Foldback Protection}
n _{Output Overvoltage Protection}
n _{Small, Low Profile Surface Mount LGA Package}
(15mm × 15mm × 2.8mm)
APPLICATIONS
n _{Telecom, Servers and Networking Equipment}
n _{Industrial and Automotive Equipment}
n _{High Power Battery-Operated Devices}
DESCRIPTION
The LTM^®4605 is a high efficiency switching mode buck-
boost power supply. Included in the package are the
switching controller, power FETs, and support components.
Operating over an input voltage range of 4.5V to 20V, the
LTM4605 supports an output voltage range of 0.8V to
16V, set by a resistor. This high efficiency design delivers
up to 5A continuous current in boost mode (12A in buck
mode). Only the inductor, sense resistor, bulk input and
output capacitors are needed to finish the design.
The low profile package enables utilization of unused space
on the bottom of PC boards for high density point of load
regulation. The high switching frequency and current
mode architecture enable a very fast transient response
to line and load changes. The LTM4605 can be frequency
synchronized with an external clock to reduce undesirable
frequency harmonics.
Fault protection features include overvoltage and foldback
current protection. The DC/DC μModule™ is offered in a
small and thermally enhanced 15mm × 15mm × 2.8mm LGA
package. The LTM4605 is Pb-free and RoHS compliant.
L, LT, LTC and LTM are registered trademarks of Linear Technology Corporation. Burst Mode
is a registered trademark of Linear Technology Corporation. μModule is a trademark of Linear
Technology Corporation. All other trademarks are the property of their respective owners.
TYPICAL APPLICATION
12V/5A Buck-Boost DC/DC μModule with 4.5V to 20V Input
V_IN
4.5V TO 20V
10μF
35V
ON/OFF
0.1μF
CLOCK SYNC
V_IN PLLIN _VOUT
FCB
RUN LTM4605
SW1
SW2
R_SENSE
SENSE⁺
SS
SGND
SENSE^–
PGND
V_FB
4.7μH
6mΩ
7.15k
10μF ⁺
35V
330μF
25V
V_OUT
12V
5A
4605 TA01
Efficiency and Power Loss vs
Input Voltage
99 _{VOUT = 12V}
8
98 ^ILOAD ^{= 5A}
f = 200kHz
7
97
6
96
5
95
4
94
3
93
92
2
91
1
90
0
5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
V_IN (V)
4605 TA01b
4605fa
1