Kenwood TS-440S Service Manual page 30

TS-440S
M B8 4 1 8 - L P20-GRA (Control u n it I C 5 0 )
EIO
JJ PD7800
T L
C I C 4 l
SN 74 LS l 38
l.
M B M 2 7 1 28 ( Control u n it I C 5 2 )
+ 1 5 V
JJ PD7800
+1 5 V
JJPD
Yo Y1
7800
1 5 14
S N 74 LS l 38
30
SEM I C O N D U CTOR
A I O
Address Low
buffer decoder
+ 5V
B A T T
Y decoder
Ao
l
X decoder
V oo
G N O
M emori o l
A l ley
1 28 x l 6 x 8
I
/ 0 ga t e
co l u m n d ecoder
I
C S B
/0 buffer
- 1 1 0
I O X
D o to -
Oo 07
D o t o o u t p u t
Pin name
O u t p u t B uffer
y
s e l ect ion
1 3 1 072 b i t
( 5 1 2 x 256 )
M e m or i a l
a l l y
S y m b o l P i n n a m e
A o - A 1 0 A d d ress i n p u t
I ( ) 1 - 1 ( )x
D ata i n /o u t
C h i p s e l e c t 1
C S 2 C h i p s e l e c t 2
W E
Write e n a b l e
V e e P o w e r ( 1 . 5 V )
G N D G N D
N C . N o c o n n ec t i o n
A d d ress i n p u t
A o - A 1 3
-
O o - 0 1
D ata o u t p u t
C E C h i p e n a b l e i n p u t
O E O u t p u t e n a b l e i n p u t
P r o g r a m i n pu t
PG M
V e e P o w e r s u p p l y
V p p P r o g r a m p o w e r s u p p l y
G N D G N D