Service manual

IC19 Sound DRAM
IC HM514270AJ-8 SOJ HITACHI
Parts No. : 315-0777-80
IC UPD424270LE-70 SOJ NEC
Parts No.: 315-0739-70
IC MN414270SJ-08 SOJ PANASONIC
Parts No. : 315-0822-80
• Top View & Pin Layout
Vss
1/015
1/014
1/013
11012
Vss
1/0ll
11010
IIOg
Input State
RAS
CAS
UWE
H
H D
H
L H
L L H
L
L
L2)
L L L2)
L L
H~L
L
H D
H~L
L D
L
H~L
H
L
H--+L
L2)
L
H-+L
L2)
L
H~L
H-+L
Output
LWE
State
D Open
H
Valid
H
Valid
L2) Open
L 2) Underlined
H--+L
Valid
D
Open
D Open
H
Valid
L2) Open
L2) Underlined
H-+L
Valid
IC HM514270Aj-7 SOJ HITACHI
Parts No.: 315-0777-70
Operation Mode
Standby
Standby
Read cycle
Early write cycle
Delayed write cycle
Read modified write cycle
RAS
onlY_ refresh 9:_cle
CAS before !RAS refresh 9:_cle
High-speed page mode read cycle
High-speed page mode early write cycle
High-speed page mode delayed write cycle
High-speed page mode read modified write cycle
1 110
8
NC
NC
CAS
oe
As
A7
As
As
A4
Note: H=High(inactive), L=Low(active), D=Don't care.
IC20 PLL
IC CUSTOM CHIP PLL HQFP
Parts No.: 315-5746
II Top View
6
28
20
15
§ §
7 14
~ ~
~--~4~--------------------~3~--~~~
OSIN1
NPSEL 1 }------1----'
DO~EL 2r----------+~====~------------~~r-~
SYSRES 3
DVOD
OSIN2
OSOUT2
EXTCLK 1}----f---'
oscsw 7)-----4-----'
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