saa4955tj NXP Semiconductors, saa4955tj Datasheet - Page 3

• Manufacturer Part Number: saa4955tj
• Description: 2.9-mbit Field Memory
• Manufacturer: NXP Semiconductors

Philips Semiconductors
BLOCK DIAGRAM
1999 Apr 29
handbook, full pagewidth
2.9-Mbit field memory
Pins 20 and 21 (V
5.5 V instead of 3.3 V. Pins 19 and 22 (V
3.3 V
V DD(O)
100 nF
V DD(P)
V DD(P)
GND O
GND P
GND P
GND
V DD
19
20
21
22
1
2
39
40
IE
internal
D0
internal
DD(P)
) should be connected to the supply voltage of the driving circuit that generates the input voltages. This could be, for instance,
D0 to D11
WRITE MINI CACHE
READ MINI CACHE
DATA INPUT AND
12-WORD ( 12)
12-WORD ( 12)
DATA OUTPUT
BUFFER ( 13)
BUFFER ( 12)
WRITE MASK
DATA MUX
Q0 to Q11
12
14 to 3
12
12
12
SAA4955TJ
1
27 to 38
12
IE
DD
mini cache write control
18
cache
transfer
12
and V
DD(O)
mini cache read control
OE
internal
) require a 3.3 V supply.
WE
17
INPUT BUFFER
PARALLEL WRITE REGISTER
PARALLEL READ REGISTER
Fig.1 Block diagram.
SERIAL WRITE REGISTER
SERIAL READ REGISTER
OE
RSTW
INPUT BUFFER
( 3)
245760-WORD ( 12)
23
MEMORY ARRAY
16
cache transfer
20-WORD ( 13)
20-WORD ( 13)
20-WORD ( 12)
20-WORD ( 12)
RE
( 4)
24
RSTR
SWCK
3
25
SRCK
15
20
20
20
20
3
26
3
(12
(12
12
12
1)
1)
SERIAL WRITE CONTROLLER
SERIAL READ CONTROLLER
IE internal
control
control
write
read
ARBITRATION
MEMORY
LOGIC
read
acknowledge
write
acknowledge
REFRESH ADDRESS
WRITE ADDRESS
READ ADDRESS
COUNTER
COUNTER
COUNTER
load write
block
address
load read
block
address
Product specification
SAA4955TJ
OSCILLATOR
refresh clock
CLOCK
internal
D0
internal
OE
internal
IE
MGK676