LTC3675
7-Channel Configurable
High Power PMIC
FEATURES
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DESCRIPTION
The LTC
®
3675 is a digitally programmable high efficiency
multioutput power supply plus dual string LED driver IC
optimized for high power single cell Li-Ion/Polymer applica-
tions. The DC/DCs consist of four synchronous buck con-
verters (1A/1A/500mA/500mA), one synchronous boost
DC/DC (1A), and one buck-boost DC/DC (1A) all powered
from a 2.7V to 5.5V input. The 40V LED driver can regulate
up to 25mA of current through two LED strings with up to
10 LEDs each. The LED driver may also be configured as
a general purpose high voltage boost converter.
DC/DC enables, output voltages, switch slew rates and
operating modes may all be independently programmed
over I
2
C or used in standalone mode via simple I/O and
power-up defaults. The buck DC/DCs may be used inde-
pendently or paralleled to achieve higher output currents
with a shared inductor. LED enable, 60dB brightness control
and up/down gradation are programmed using I
2
C. Alarm
levels for low V
IN
and high die temperature may also be
programmed via I
2
C with a maskable interrupt output to
monitor DC/DC and system faults.
Pushbutton ON/OFF/RESET control and a power-on reset
output provide flexible and reliable power-up sequenc-
ing. The LTC3675 is available in a low profile (0.75mm),
thermally enhanced 44-lead 4mm
×
7mm QFN package.
L,
LT, LTC, LTM, Linear Technology, the Linear logo and Burst Mode are registered trademarks of
Linear Technology Corporation and Hot Swap is a trademark of Linear Technology Corporation. All
other trademarks are the property of their respective owners.
Four Monolithic Synchronous Buck DC/DCs
(1A/1A/500mA/500mA)
Buck DC/DCs Can Be Paralleled to Deliver Up to
2× Current with a Single Inductor
Independent 1A Boost and 1A Buck-Boost DC/DCs
Dual String I
2
C Controlled 40V LED Driver
I
2
C Programmable Output Voltage, Operating
Mode, and Switch Node Slew Rate for All DC/DCs
I
2
C Read Back of DC/DC, LED Driver, Fault Status
I
2
C Programmable V
IN
and Die Temperature
Warnings
Maskable Interrupts to Report DC/DC, V
IN
and Die
Temperature Faults
Pushbutton ON/OFF/RESET
Always-On 25mA LDO
Low Quiescent Current: 16μA (All DC/DCs Off)
4mm
×
7mm
×
0.75mm 44-Lead QFN Package
APPLICATIONS
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High Power (5W to 10W) Single Cell Li-Ion/Polymer
Applications
Portable Industrial Applications, Handy Terminals,
Portable Instruments
Multioutput Low Voltage Power Supplies
TYPICAL APPLICATION
2.7V TO 5.5V
3
V
IN
I
2
C
EN1
EN2
EN3
EN4
ENBB
IRQB
RSTB
WAKE
PBSTAT
ONB
PUSH BUTTON
•
•
•
CT
0.01μF
EXPOSED PAD
LED1
LED2
3675 TA01
DIGITAL
CONTROL
SW1
SW2
SW3
SW4
LTC3675
SW5
VOUT5
SWAB6
SWCD6
VOUT6
LDO_OUT
SW7
0.425V TO V
IN
, 1A MAX
0.425V TO V
IN
, 1A MAX
0.425V TO V
IN
, 500mA MAX
0.425V TO V
IN
, 500mA MAX
V
IN
V
IN
TO 5.35V, 1A MAX
2.65V TO 5.25V, 1A MAX
0.8V TO V
IN
, 25mA MAX
V
IN
•
•
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UP TO 10 LEDS
PER STRING
3675fa
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LINEAR [ LINEAR INTEGRATED SYSTEMS ]
