LT3668
28
3668fa
For more information www.linear.com/LT3668
LINEAR TECHNOLOGY CORPORATION 2014
LT 0215 REV A • PRINTED IN USA
Linear Technology Corporation
1630 McCarthy Blvd., Milpitas, CA 95035-7417
(408) 432-1900
●
FAX: (408) 434-0507
●
www.linear.com/LT3668
RELATED PARTS
TYPICAL APPLICATION
PART NUMBER DESCRIPTION COMMENTS
LT3667 40V, 400mA Step-Down Switching Regulator with Dual Fault
Protected LDOs
V
IN
: 4.3V to 40V, V
OUT(MIN)
= 0.8V, I
Q
= 50mA, I
SD
< 1µA,
MSOP-16E, 3mm × 5mm QFN-24,
LT3500 36V
(40V
MAX
), 2A (I
OUT
), 2.2MHz Step-Down Switching Regulator
with LDO Controller
V
IN
: 3V to 36V, V
OUT(MIN)
= 0.8V, I
Q
= 2.5mA, I
SD
< 12µA,
3mm × 3mm DFN-10, MSOP-16E
LT1939 25V, 2A (I
OUT
), 2.2MHz Step-Down Switching Regulator with LDO
Controller
V
IN
: 3V to 25V, V
OUT(MIN)
= 0.8V, I
Q
= 2.5mA, I
SD
< 12µA,
3mm × 3mm DFN-10, MSOP-16E
LT3694 36V (70V
MAX
), 2.6A (I
OUT
), 2.5MHz Step-Down Switching
Regulator with Dual LDO Controller
V
IN
: 4V to 36V, V
OUT(MIN)
= 0.8V, I
Q
= 1mA, I
SD
< 1µA,
4mm × 5mm QFN-28, TSSOP-20E
LT3507/LT3507A 36V, 2.5MHz, T
riple (2.4A + 1.5A + 1.5A (I
OUT
) with LDO
Controller High Efficiency Step-Down DC/DC Converter
V
IN
: 4V to 36V, V
OUT(MIN)
= 0.8V, I
Q
= 7mA, I
SD
= 1µA,
5mm × 7mm QFN-38
LT3970 40V, 350mA (I
OUT
), 2.2MHz Step-Down Switching Regulator with
I
Q
= 2.5µA
V
IN
: 4.2V to 40V, V
OUT(MIN)
= 1.2V, I
Q
= 2.5µA, I
SD
< 1µA,
3mm × 2mm DFN, MSOP-10
LT3502/LT3502A 40V, 500mA (I
OUT
), 1.1MHz/2.2MHz Step-Down Switching
Regulator
V
IN
: 3V to 40V, V
OUT(MIN)
= 0.8V, I
Q
= 1.5mA, I
SD
< 1µA,
2mm × 2mm DFN-8, MSOP-10E
3668 TA06
EN2/ILIM2 EN3/ILIM3GND
5V
200mA
(FAULT PROTECTED)
5V
200mA
(FAULT PROTECTED)
C5
10µF
C4
10µF
IN1
LT3668
BOOST
SW
DA
IN3/BD
IN2
FB1
EN
PG
RT
ADJ2
OUT2
OUT3
ADJ3
C1
4.7µF
C2
0.22µF
C6
22pF
L1
27µH
R2
1.18M
D1
DFLS160
R3
294k
R
T1
174k
f = 600kHz
V
IN
7V TO 40V
C7
4.7µF
C8
0.47µF
C9
22µF
5V
750mA
C3
22µF
ON OFF
ON OFF
BOOST
SW
BD
OUT
V
OUT
EN/UVLO
PG
LT3973-5
GND
C1 - C9: X5R OR X7R
L1: SUMIDA CDRH5D28R/HP
RT
V
IN
L2
15µH
R
T2
215k
f=600kHz
5V/0.75A Supply with Tw o 0.2A Tracking Outputs
