Datasheet

LT3745-1
12
37451f
BLOCK DIAGRAM
32
3534 3031
1
15 33 16 14
C
SS
C
VCC
R
FB2
R
FB1
V
CC
V
CC
SS
ISN RTISP SYNC
12µA
EN/UVLO FB PWMCK
+
SDI
+
SDI
–
17
PWMCK
–
LDI
OT
STATUS
INFO
(FAULT
LED
XX
)
x
SCKI
PRECHG
V
SS
< 1V
(V
IN
-V
CAP
)
V
IN
V
IN
C
IN
R
S
M1
L
D1
GATE
CAP
6.8V
1.205V
I
SET
T
SET
V
PTAT
I
REF
OT
UV
1.210V
+ –
REFERENCE BIAS
AND UVLO
RAMP OSC
S R
Q
+
–
+ –
+
–
R
T
DRIVER
G
M
1
+
–
37 38 36
C
CAP
C
OUT
V
OUT
PG
POR
G
M
2
0.7V LED00 LED01 LED15
EN
+ – –
. . .
–
C0
SHIFT
REGISTER
C1
192192
16X
16X
FS FS
SDI
SCKO
SDO
FS
EN
GS REGISTER DC REGISTER
12-BIT PWM
DIMMING
CONSTANT CURRENT
SINK
6-BIT DOT
CORRECTION
OPEN/SHORT
LED
12 12
EN
6 6
FAULT LED
XX
PWMCK
I
REF
LED
XX
GND
37451 BD
40 39
+
–
+
–
R
ISET
R
TSET
S R
Q
12 13
SCKI
+
SCKI
–
10 11 20 21
SCKO
+
SCKO
–
18 19
41
SDO
+
SDO
–