LT3420 LINER [Linear Technology], LT3420 Datasheet - Page 7

• Manufacturer Part Number: LT3420
• Description: Photoflash Capacitor Chargers with Automatic Refresh
• Manufacturer: LINER [Linear Technology]

BLOCK DIAGRA S
CHARGE
CHARGE
V
V
CC
CC
C3
C2
C2
C3
CT
CT
10
10
9
4
9
4
V
V
CC
CC
REFRESH
SHOT
REFRESH
SHOT
ONE-
ONE-
TIMER
TIMER
Q
Q
S
S
CHIP
ENABLE
CHIP
ENABLE
MASTER
MASTER
LATCH
LATCH
V
V
W
BAT
BAT
Q
R
Q
R
DONE
DONE
BLOCK
ENABLE
BLOCK
ENABLE
8
8
Q5
Q5
C1
C1
A3
A3
2
Figure 4. Block Diagram, LT3420-1
2
Figure 3. Block Diagram, LT3420
V
V
D3
D3
BAT
BAT
–
–
+
+
3
3
Q3
Q3
R
R
FB
FB
Q2
REFERENCE
REFERENCE
1
1
R
R
1V
REF
REF
1V
R2
R2
SHOT
SHOT
ONE-
ONE-
POWER DELIVERY BLOCK
POWER DELIVERY BLOCK
Q4
Q4
R
R
S
S
Q
Q
R1
R1
DRIVER
DRIVER
A1
A2
A1
A2
–
–
+
–
+
+
+
–
20mV
10mV
20mV
10mV
+ –
+ –
+ –
+ –
LT3420/LT3420-1
6
6
Q1
Q1
SW
SW
0.02
0.66
0.014
0.25
LT3420-1
PRIMARY
PRIMARY
LT3420
5
7
5
7
GND
SEC
GND
3420 F04
SEC
3420 F03
1:10
1:12
T1
T1
SECONDARY
PHOTOFLASH
SECONDARY
PHOTOFLASH
CAPACITOR
CAPACITOR
D1
D1
C4
C4
+
+
3420fa
7
V
V
OUT
OUT