Datasheet

16
LT3420/LT3420-1
3420fb
3420 TA01
+
V
CC
CHARGE
DONE
SEC
R
REF
LT3420
V
BAT
R
FB
SW
C
T
GND
C2
4.7µF
C3
0.1µF
C1
4.7µF
V
BAT
1.8V TO 6V
V
CC
2.5V TO 10V
R1
52.3k
2
4
9
8
10 5
36
7
1
2
4
9
8
10 5
36
7
1
T1
1:12
320V
3, 4
5, 6 8
1
R2
2k
D1
C1, C2, C4, C5, C6, C7: 4.7µF, X5R or X7R, 10V
T1-T3: TDK SRW10EPC-U01H003 FLYBACK TRANSFORMER
D1-D3: VISHAY GSD2004S SOT-23
DUAL DIODE. DIODES CONNECTED IN SERIES
Q1: 2N3904 OR EQUIVALENT
* CAN CHARGE ANY SIZE PHOTOFLASH CAPACITOR
** USE AS MANY SLAVE CHARGERS AS NEEDED.
DANGER HIGH VOLTAGE
OPERATION BY HIGH VOLTAGE
TRAINED PERSONEL ONLY
650µF*
350V
PHOTOFLASH
CAPACITOR
V
CC
CHARGE
DONE
SEC
R
REF
LT3420
V
BAT
R
FB
SW
C
T
GND
C5
4.7µF
C4
4.7µF
V
BAT
T2
1:12
3, 4
5, 6
3, 4
5, 6
8
1
2
4
9
8
10 5
36
7
1
1
D2
SLAVE**
CHARGER
MASTER
CHARGER
SLAVE**
CHARGER
V
CC
CHARGE
DONE
SEC
R
REF
LT3420
V
BAT
R
FB
SW
C
T
GND
C7
4.7µF
C6
4.7µF
V
BAT
T3
1:12
8
1
D3
R4
100k
R3
100k
V
CC
V
CC
Q1
2N3904
CHARGE
TYPICAL APPLICATIO S
U
Professional Charger uses Multiple LT3420 Circuits in Parallel to Charge Large Photoflash Capacitors Quickly