20
LT3420/LT3420-1
3420fb
PART NUMBER DESCRIPTION COMMENTS
LTC
®
3400/LTC3400B 600mA (I
SW
), 1.2MHz, Synchronous Step-Up V
IN
= 0.85V to 5V, V
OUT(MAX)
= 5V, I
Q
= 19µA/300µA,
DC/DC Converters I
SD
= <1µA, ThinSOT
TM
Package
LTC3401/LTC3402 1A/2A (I
SW
), 3MHz, Synchronous Step-Up V
IN
= 0.5V to 5V, V
OUT(MAX)
= 6V, I
Q
= 38µA, I
SD
= <1µA,
DC/DC Converters MS Package
LTC3405/LTC3405A 300mA (I
OUT
), 1.5MHz, Synchronous Step-Down 95% Efficiency, V
IN
= 2.7V to 6V, V
OUT(MIN)
= 0.8V , I
Q
= 20µA,
DC/DC Converters I
SD
= <1µA, ThinSOT Package
LTC3406/LTC3406B 600mA (I
OUT
), 1.5MHz, Synchronous Step-Down 95% Efficiency, V
IN
= 2.5V to 5.5V, V
OUT(MIN)
= 0.6V, I
Q
= 20µA,
DC/DC Converters I
SD
= <1µA, ThinSOT Package
LTC3407 Dual 600mA (I
OUT
), 1.5MHz, Synchronous Step-Down 95% Efficiency, V
IN
= 2.5V to 5.5V, V
OUT(MIN)
= 0.6V, I
Q
= 40µA,
DC/DC Converter I
SD
= <1µA, ThinSOT Package
LTC3411 1.25A (I
OUT
), 4MHz, Synchronous Step-Down 95% Efficiency, V
IN
= 2.5V to 5.5V, V
OUT(MIN)
= 0.8V, I
Q
= 60µA,
DC/DC Converter I
SD
= <1µA, MS Package
LTC3425 5A (I
SW
), 8MHz, Multiphase Synchronous Step-Up 95% Efficiency, V
IN
= 0.5V to 4.5V, V
OUT(MIN)
= 5.25V, I
Q
= 12µA,
DC/DC Converter I
SD
= <1µA, QFN Package
LTC3440/LTC3441 600mA/1A (I
OUT
), 2MHz/1MHz, Synchronous Buck-Boost 95% Efficiency, V
IN
= 2.5V to 5.5V, V
OUT(MIN)
= 2.5V, I
Q
= 25µA,
DC/DC Converters I
SD
= <1µA, MS Package
LT3464 85mA (I
SW
), Constant Off-Time, High Efficiency V
IN
= 2.3V to 10V, V
OUT(MAX)
= 34V, I
Q
= 25µA, I
SD
= <0.5µA,
Step-Up DC/DC Converter with Integrated Schottky ThinSOT Package
and Output Disconnect
LTC3467 1.1A (I
SW
), 1.3MHz, High Efficiency Step-Up V
IN
= 2.4V to 16V, V
OUT(MAX)
= 40V, I
Q
= 1.2mA, I
SD
= <1µA,
DC/DC Converter ThinSOT Package
LTC3468/LTC3468-1/ Photoflash Capacitor Charger in ThinSOT Fast Photoflash Charge Times; 4.6sec for LT3468, 5.5sec for
LTC3468-2 LT3468-1, 5.7sec for LT3468-2
ThinsSOT is a trademark of Linear Technology Corporation.
Linear Technology Corporation
1630 McCarthy Blvd., Milpitas, CA 95035-7417
(408) 432-1900
●
FAX: (408) 434-0507
●
www.linear.com
© LINEAR TECHNOLOGY CORPORATION 2002
LT/LT 0305 REV B • PRINTED IN USA
RELATED PARTS
LT3420-1 Photoflash Circuit Uses Tiny (3mm Tall) Transformer
3420 TA04
+
V
CC
CHARGE
DONE
SEC
R
REF
LT3420-1
V
BAT
R
FB
SW
C
T
GND
C2
4.7µF
0.1µF
C1
4.7µF
V
BAT
1.8V TO 6V
V
CC
2.5V TO 6V
CHARGE
DONE
60.4k
T1
1:10.2
320V
8
5
4
1
2k
D1
C1, C2: 4.7µF, X5R or X7R, 6.3V
C3: RUBYCON 100µF PHOTOFLASH CAPACITOR
T1: TDK LDT565630T-002 FLYBACK TRANSFORMER
D1: VISHAY GSD2004S SOT-23
DUAL DIODE. DIODES CONNECTED IN SERIES
DANGER HIGH VOLTAGE
OPERATION BY HIGH VOLTAGE
TRAINED PERSONEL ONLY
C3
100µF
330V
PHOTOFLASH
CAPACITOR
4
9
8
10 5
1
7
632
V
BAT
(V)
2
TIME (s)
6
3420 TA05
3
4
5
10
8
6
4
2
0
V
OUT
CHARGED
FROM 50V TO 320V
C
OUT
= 100µF
C
OUT
= 40µF
Charge Time
U
TYPICAL APPLICATIO
