NAD T748 Service Manual page 39

IC BLOCK DIAGRAMS
V3
FB3
12V DC Supply
from enable logic
from enable logic
from enable logic
GND
VIN
VIN
VIN
VIN
GND
LX3
LX3
VIN3
VIN3
BST3
EN3
FUNCTIONAL BLOCK DIAGRAM
AGND
V3V
INTERNAL
V7V
VOLTAGE RAILS
VIN1
SS1
EN1
Rlim1
VIN2
SS2
EN2
Rlim2
VIN3
SS3
EN3
Rlim3
VIN
PG
Generator
PGOOD
EN2
BST2
VIN2
LX2
LX2
TPS65251
LX1
LX1
VIN1
BST1
EN1
BUCK1
BUCK2
BUCK3
PFM mode
GND
2-27
FB2
VIN2
VIN1
ROSC
OSC
SYNC
BST1
LX1
LX1
FB1
COMP1
BST2
LX2
LX2
FB2
COMP2
BST3
LX3
LX3
FB3
COMP3
LOW_P
V2
V1
FB1
Vout BUCK1
Vout BUCK2
Vout BUCK3