Harman Kardon HK 990/230, Service Manual

Page: 37 / 141

Rev. 1.5 / Feb. 2005 5
Synchronous DRAM Memory 64Mbit (4Mx16bit)
HY57V641620E(L/S)T(P)-xI Series
FUNCTIONAL BLOCK DIAGRAM
1Mbit x 4banks x 16 I/O Synchronous DRAM
Internal Row
Counter
Column
Pre
Decoder
Column Add
Counter
Self refresh
logic & timer
Sense AMP & I/O Gate
I/O Buffer & Logic
Address
Register
Burst
Counter
Mode Register
State Machine
Address Buffers
Bank Select
Column Active
Row Active
CAS Latency
CLK
CKE
CS
RAS
CAS
WE
U/LDQM
A0
A1
BA1
BA0
A11
Row
Pre
Decoder
Refresh
DQ0
DQ15
X-Dec
oder
X-Dec
oder
X-Dec
oder
X-Dec
oder
Y-Decoder
1Mx16 BANK 0
1Mx16 BANK 1
1Mx16 BANK 2
1Mx16 BANK 3
Memory
Cell
Array
Data Out Control
Pipe Line
Control
3 5