Datasheet

LT3579/LT3579-1
42
35791fa
For more information www.linear.com/LT3579
 LINEAR TECHNOLOGY CORPORATION 2010
LT 0514 REV A • PRINTED IN USA
Linear Technology Corporation
1630 McCarthy Blvd., Milpitas, CA 95035-7417
[phone]
●
FAX: [phone]
●
www.linear.com/LT3579
RELATED PARTS
PART NUMBER DESCRIPTION COMMENTS
LT3581 3.3A (I
SW
), 42V, 2.5MHz, High Efficiency
Step-Up DC/DC Converter
V
IN
: 2.5V to 22V, V
OUT(MAX)
= 42V, I
Q
= 1.9mA, I
SD
= < 1µA, 4mm × 3mm DFN-14,
MSOP-16E
LT3580 2A (I
SW
), 42V, 2.5MHz, High Efficiency Step-Up
DC/DC Converter
V
IN
: 2.5V to 32V, V
OUT(MAX)
= 42V, I
Q
= 1mA, I
SD
= < 1µA, 3mm × 3mm DFN-8,
MSOP-8E
LT3479 3A (I
SW
), 40V, 3.5MHz, High Efficiency Step-Up
DC/DC Converter
V
IN
: 2.5V to 24V, V
OUT(MAX)
= 40V, I
Q
= 5mA, I
SD
= < 1µA, 4mm × 3mm DFN-14,
TSSOP-16E
TYPICAL APPLICATION
1MHz SEPIC Converter Generates a 12V Output from
a 9V to 16V Input
D1
L
2
6.8µH
0.22µF
47pF
L1
6.8µH
V
OUT
12V
1.9A*
C
VIN
4.7µF
V
IN
3.3V TO V
PWR
V
PWR
9V TO 16V
V
IN
SW1 SW2
35791 TA29
LT3579
86.6k
9.53k
130k
C1
4.7µF
SHDN
FAULT
CLKOUT
GATE
FB
VC
SYNC GND SS
RT
2.2nF
•
•
C
OUT
10µF
×3
100k
C
PWR
4.7µF
C
PWR
: 4.7µF, 25V, X7R, 1206
C
VIN
: 4.7µF, 25V, X7R, 1206
C1: 4.7µF, 25V, X7R, 1206
C
OUT
: 10µF, 25V, X7R, 1210
D1: DIODES INC MBRM360
L1, L2: COOPER BUSSMANN DRQ125-6R8-R
LINE REGULATION (V
IN
= 5V, I
OUT
= 1A) = 0.017%/V
LOAD REGULATION (V
PWR
= 12V, V
IN
= 5V) = –0.23%/A
*MAX OUTPUT CURRENT
V
PWR
= 9V V
PWR
= 12V
V
IN
= 3.3V TO 5V 1.6A 1.9A
V
IN
= V
PWR
1.4A 1.4A
LOAD CURRENT (A)
0
20
EFFICIENCY (%)
POWER LOSS (W)
60
70
80
90
50
40
30
100
0
1.6
2
2.4
2.8
1.2
0.8
0.4
3.2
0.75 1 1.25 1.5 1.75 20.25 0.5
35791 TA30
V
PWR
= 12V
V
IN
= 5V
Efficiency and Power Loss