Datasheet
LT3844
24
3844fb
Linear Technology Corporation
1630 McCarthy Blvd., Milpitas, CA 95035-7417
(408) 432-1900
●
FAX: (408) 434-0507
●
www.linear.com
© LINEAR TECHNOLOGY CORPORATION 2006
LT 0309 REV B • PRINTED IN USA
RELATED PARTS
TYPICAL APPLICATION
12V to 48V 50W Step-Up Converter with 400kHz Switching Frequency
4
R6
40k
R2
383k
R1
10k
V
IN
C
SS
BURST_EN
V
FB
V
C
SYNC
f
SET
BOOST
TG
SW
V
CC
PGND
SENSE
+
SENSE
–
SGND
M1
D2
3844 TA05
LT3844
SHDN
1
3
2
5
6
7
8
16
15
14
13
12
11
10
9
C3
4700pF
C2
120pF
C5
2.2μF
25V
C4
4700pF
C1
0.1μF
25V
C
OUT1
330μF
C
OUT2
220μF
M1 = VISHAY, Si7370DP
L1 = VISHAY, IHLP5050FD-01
D2 = DIODES INC., PDS560
C
IN
= SANYO, 25SVP33M
C
OUT1
= SANYO, 63CE220FST
C
OUT2
= TDK, C4532X7R2A225K
R
SENSE
= IRC, LRF2512-01-R010-F
C
IN
33μF
25V
s2
V
IN
12V
R
SENSE
0.01Ω
L1
6.8μH
V
OUT
48V
50W
D1
BAV99
R4
4.7M
R5
33.2k
+
+
PART NUMBER DESCRIPTION COMMENTS
LT1339 High Power Synchronous DC/DC Controller V
IN
up to 60V, Drivers 10000pF Gate Capacitance, I
OUT
< 20A
LTC1624 Switching Controller Buck, Boost, SEPIC, 3.5V ≤ V
IN
≤ 36V; 8-Lead SO Package
LTC1702A Dual 2-Phase Synchronous DC/DC Controller 550kHz Operation, No R
SENSE
, 3V < V
IN
< 7V, I
OUT
< 20A
LTC1735 Synchronous Step-Down DC/DC Controller 3.5V < V
IN
< 36V, 0.8V < V
OUT
< 6V, Current Mode, I
OUT
< 20A
LTC1778 No R
SENSE
Synchronous DC/DC Controller 4V < V
IN
< 36V, Fast Transient Response, Current Mode, I
OUT
< 20A
LT3010 50mA, 3V to 80V Linear Regulator 1.275V < V
OUT
< 60V, No Protection Diode Required,
8-Lead MSOP Package
LT3430/LT3431 Monolithic 3A, 200kHz/500kHz Step-Down Regulator 5.5V < V
IN
< 60V, 0.1Ω Saturation Switch, 16-Lead SSOP Package
LT C
®
3703/LTC3703-5 100V Synchronous Switching Regulator Controllers No R
SENSE
, Voltage Mode Control, GN16 Package
LT3724 High Voltage Current Mode Switching Regulator
Controllers
V
IN
up to 60V, I
OUT
≤ 5A, 16-Lead TSSOP FE Package,
Onboard Bias Regulator, Burst Mode Operation, 200kHz Operation
LT3800 High Voltage Synchronous Regulator Controller V
IN
up to 60V, I
OUT
≤ 20A, Current Mode, Onboard Bias Regulator,
Burst Mode Operation, 16-Lead TSSOP FE Package