Onkyo TX-NR901 Service Manual page 78

IC BLOCK DIAGRAMS AND DESCRIPTIONS
Q7100 TC74VHC541FT(Octal bus buffer)
G1 1
2
A1
3
A2
A3 4
A4 5
6
A5
A6 7
A7 8
A8 9
GND 10
Q701,Q751 TC74VHC74FT(Dual D-FF with preset and clear)
1CLR
1
1D
2
CK D
Q Q
1CK 3
1PR
4
1Q
5
CK D
1Q 6
Q Q
GND
7
Q121 TC74VHCT00A(2-input NAND gate)
1A 1
2
1B
3
1Y
2A 4
5
2B
6
2Y
7
GND
A B
L L
L H
H L
H H
INPUTS
20 Vcc
19 G2
G1 G2
18 Y1
H X
17
Y2
H
X
16
Y3
L
L
15
Y4
L
L
14
Y5
X :Don't care
13
Y6
Z :High impedance
12
Y7
11
Y8
14 Vcc
CLR
13 2CLR
L
12 2D
H
11 2CK
L
10 2PR
H
H
9 2Q
H
8 2Q
Vcc
14
4B
13
4A
12
4Y
11
3B
10
3A
9
3Y
8
Y
H
H
H
L
Q610 TC7S02FU(2-input NOR gate)
IN B
OUTPUT
An
IN A
X Z
X Z
GND
H H
L L
INPUTS OUTPUTS
PR D CK Q
H X X L
L X X H
L X X H
H L L
H H H
H X Qn
X: Don't care
Q609 TC7W14FU (Schmidt Inverter)
1A 1
3Y 2
2A 3
GND 4
TX-NR901
1 5
Vcc
2
3 4 OUT Y
A B Y
L L H
L H L
H L L
H H L
FUNCTION
Q
H CLEAR
L PRESET
H
H
L
Qn NO CHANGE
8
Vcc
7
1Y
6
3A
5
2Y