NAD C 541 Service Manual page 17

U403: 74HC00
A1 1
B1 2
Y1 3
A2 4
B2 5
Y2 6
GND 7
U401: LC866008C
48 47 46 45 44 43 42 41 40 39 38 37 36 35 34 33
TEST 1
49
RES
50
XT1
51
XT2
52
VSS
53
CF1
54
CF2
55
VDD
56
P80/AN0
57
P81/AN1
58
P82/AN2
59
P83/AN3 60
P70/INTO 61
P71/INT1 62
P72/INT2/TOIN 63
P73/INT3/TOIN 64
1 2 3 4
U305-U306: OPA2604
AMPLIFIER 1
OUTPUT 1
INVERTING
2
INPUT
– +
NON-INVERTING
3
INPUT
4
V –
14 VCC
13 B4
12 A4
11 Y4
10 B3
9 A3
8 Y3
5 6 7 8 9 10 11 12 13 14 15 16
AMPLIFIER 2
8
V +
7
OUTPUT
+ –
INVERTING
6
INPUT
NON-INVERTING
5
INPUT
U701: LB1641
5
IN1
1
GND
IC401: System Block Diagram LC8660/08C
S29
32
S28
31
S27
30
S26
29
S25
28
Base Timer
S24
27
S23
26
SIO0
S22
25
SIO1
S21
24
Timaer 0
S20
23
S19
22
Timaer 1
21 S18
ADC
20 S17
19 S16
INT0-3
18 VP
Noise Filter
17 VDDVPP
Real Time
Service
XRAM
(128 bytes)
VFD Controller
High Voltage
Output
19
P1 OUT1 VCC2 OUT2
3 2 8 10
Input logic circuit
Interrupt Control
Stand-by Control
CF
Clock
RC
Generator
X'tal
Bus Interface
Port1
Port7
Port8
Bus
P2 VCC1
9 7
4
VZ
6
IN2
IR PLA
ROM
PC
Bus
ACC
B Reg
C Reg
ALU
PSW
RAR
RAM
Stack Pointer
PORT 0
Watcher Dog Timer