LT3641
28
3641fa
Linear Technology Corporation
1630 McCarthy Blvd., Milpitas, CA 95035-7417
(408) 432-1900
●
FAX: (408) 434-0507
●
www.linear.com
© LINEAR TECHNOLOGY CORPORATION 2011
LT 1111 REV A • PRINTED IN USA
RELATED PARTS
TYPICAL APPLICATION
2MHz 3.3V/0.8A and 0.8V/1.2A Buck Regulators
3641 TA05
SYNC
WDE
PGOOD2
1nF
1nF
32.4k
V
OUT2
0.8V/1.2A
V
OUT1
3.3V/0.8A
22μF
RST1
RST2
WDO
WDI FB2
CWDT CPOR RT GND SS2 SS1
SW2
SW1EN/UVLO V
IN
SW
LT3641
BST
V
IN2
FB1
0.47μH
49.9k
16.5k
80.6k
49.9k
3.3μH
0.22μF
DA
22μF
4.7μF
V
IN
4V TO 42V*
EN2
* RESTRICTIONS APPLY FOR INPUT VOLTAGES ABOVE 42V
PART NUMBER DESCRIPTION COMMENTS
LT3640 35V, 55V Transient Protection, 1.3A High Voltage Channel and
1.1A Low Volume Channel
V
IN
: 4V to 35V, Transient to 55V, V
OUT(MIN)
= 0.6V, I
Q
= 290mA, 1μA,
4mm × 5mm QFN-28, TSSOP-28E Packages
LT3689 36V, 60V Transient Protection, 800mA, 2.2MHz High
Effi ciency MicroPower Step-Down DC/DC Converter with
POR Reset and Watchdog Timer
V
IN
: 3.6V to 36V, Transient to 60V, V
OUT(MIN)
= 0.8V, I
Q
= 75μA,
I
SD
< 1μA, 3mm × 3mm QFN-16 Package
LT3686/LT3686A 37V, 55V
MAX
, 1.2A, 2.5MHz High Effi ciency Step-Down DC/
DC Converter
V
IN
: 3.6V to 37V, Transient to 55V, V
OUT(MIN)
= 1.21V, I
Q
= 1.1mA,
I
SD
< 1μA, 3mm × 3mm DFN-10 Package
LT3682 36V, 60V
MAX
, 1A, 2.2MHz High Effi ciency Micropower
Step-Down DC/DC Converter
V
IN
: 3.6V to 36V, V
OUT(MIN)
= 0.8V, I
Q
= 75μA, I
SD
< 1μA, 3mm × 3mm
DFN-12 Package
LT3971 38V, 1.2A (I
OUT
), 2MHz, High Effi ciency Step-Down DC/DC
Converter with Only 2.8μA of Quiescent Current
V
IN
: 4.2V to 38V, V
OUT(MIN)
= 1.2V, I
Q
= 2.8μA, I
SD
< 1μA, 3mm × 3mm
DFN-10, MSOP-10E Packages
LT3991 55V, 1.2A (I
OUT
), 2MHz, High Effi ciency Step-Down DC/DC
Converter with Only 2.8μA of Quiescent Current
V
IN
: 4.2V to 55V, V
OUT(MIN)
= 1.2V, I
Q
= 2.8μA, I
SD
< 1μA, 3mm × 3mm
DFN-10, MSOP-10E Packages
