LT3959
26
3959fa
For more information www.linear.com/LT3959
LINEAR TECHNOLOGY CORPORATION 2012
LT 0613 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/LT3959
relaTeD parTs
Typical applicaTion
PART NUMBER DESCRIPTION COMMENTS
LT3957 Boost, Flyback, SEPIC and Inverting Converter
with 5A, 40V Switch
3V ≤ V
IN
≤ 40V, 100kHz to 1MHz Programmable Operation Frequency,
5mm × 6mm QFN Package
LT3958 Boost, Flyback, SEPIC and Inverting Converter
with 3.3A, 84V Switch
5V ≤ V
IN
≤ 80V, 100kHz to 1MHz Programmable Operation Frequency,
5mm × 6mm QFN Package
LT3759 Boost, Flyback, SEPIC and Inverting Controller
1.6V ≤ V
IN
≤ 42V, 100kHz to 1MHz Programmable Operation Frequency,
MSOP-12E Package
LT3758 Boost, Flyback, SEPIC and Inverting Controller
5.5V ≤ V
IN
≤ 100V, 100kHz to 1MHz Programmable Operation Frequency,
3mm × 3mm DFN-10 and MSOP-10E Packages
LT3757 Boost, Flyback, SEPIC and Inverting Controller
2.9V ≤ V
IN
≤ 40V, 100kHz to 1MHz Programmable Operation Frequency,
3mm × 3mm DFN-10 and MSOP-10E Packages
LT3748 100V Isolated Flyback Controller 5V ≤ V
IN
≤ 100V, No Opto Flyback , MSOP-16 with High Voltage Spacing
LT3798 Off-Line Isolated No Opto-Coupler Flyback
Controller with Active PFC
V
IN
and V
OUT
Limited Only by External Components
2.5V to 8V Input, 12V Output Boost Converter
DRIVE
LT3959
L1
10µH
V
IN
SW
L1: COILTRONICS DR125-100
D1: VISHAY SILICONIX 20BQ030
GND
FBX
RT SS
INTV
CC
EN/UVLO
PGOOD
SYNC
SGND
R4
121k
V
C
3959 TA05
D1
GNDK
R3
124k
R5
47k
R
T
27.4k
300kHz
C
VCC
4.7µF
10V
X5R
C
SS
0.22µF
R
C
3.4k
C
C
22nF
R2
105k
R1
15.8k
C
OUT
47µF
16V
X5R
×2
V
OUT
12V
500mA, 2.5V ≤ V
IN
< 5V
1A, 5V ≤ V
IN
≤ 8V
V
IN
2.5V TO 8V
C
IN
22µF
16V
X5R
Efficiency vs Output Current Load Step Response at V
IN
= 8V
OUTPUT CURRENT (mA)
0
EFFICIENCY (%)
85
95
100
600 800
3759 TA05b
75
200 400
1000
80
90
70
V
IN
= 5V
500µs/DIV
V
OUT
500mV/DIV
(AC)
I
OUT
500mA/DIV
0.2A
0.8A
3959 TA05c
