Rainbow Electronics MAX8742 - Manual (Page 14)

MAX8741/
M
AX8742
500kHz Multi-Output Power-Supply Controllers
with High Impedance in Shutdown
14 ______________________________________________________________________________________
LPF
50kHz
REF
1.75V
2.388V
R3
R4
-
+
+
-
4.5V
REF
2.5V
REF
333kHz
TO
500kHz
OSC
5V
PWM
LOGIC
5V
LINEAR
REG
V L
BST3
DH3
LX3
DL3
3.3V
V L
ON/OFF
INPUT
7V TO 24V
5V ALWAYS ON
CSL5
SHDN V+ SYNC
12V
LINEAR
REG
12V
13V
BST5 RAW 15V
DH5
DL5
V L
PGND
CSH5
CSL5
CSH3
CSL3
FB5
RESET
SEQ
2.6V
1V
0.6V 0.6V
V
L
GND RUN/ON3
TIME/ON5
REF
LX5 5V
12OUT
V
DD
IN
SECFB
3.3V
PWM
LOGIC
REF
OUTPUTS
UP
-
+ -
+
+
-
-
+
-
+
+
-
+
-
LPF
50kHz
TIMER
POWER-ON
SEQUENCE
LOGIC
R1
R2
FB3
-
+
+
-
MAX8742
OV/UV
FAULT
2.68V
Figure 2. MAX8742 Functional Diagram