AS42C4064 883C
64K x 4 VRAM
AUSTIN SEMICONDUCTOR, INC.
Limited Supply - Consult Factory
EQUIVALENT FUNCTIONAL BLOCK DIAGRAM
8
DRAM
OUTPUT
BUFFERS
4
8
COLUMN DECODER
4
M
A
S
K
256
SENSE AMPLIFIERS
256
WRITE
CONTROL
LOGIC
DQ1
DQ4
4
4
DRAM
INPUT
BUFFERS
4
256 x 256 x 4
DRAM ARRAY
256
8
8
A0-A7
RAS
TIMING
GENERATOR
&
CONTROL
LOGIC
CAS
TR/OE
ME/WE
SC
SE
256
8
REFRESH
COUNTER
TRANSFER
CONTROL
TRANSFER GATE
SAM
*
SAM
OUTPUT
BUFFERS
256
SDQ1
SDQ4
SAM LOCATION
DECODER
4
4
4
SAM
INPUT
BUFFERS
8
8
8
* The SAM register is 512 bits wide. Auto wrap around will not occur at the 257th serial clock pulse, thus requiring the serial
pointer to be reset back to zero, using a read or write transfer cycle.
AS42C4064 883C
REV. 3/97
DS000013
Austin Semiconductor, Inc., reserves the right to change products or specifications without notice.
.
3-2
MICROSS [ MICROSS COMPONENTS ]
