鈥?/div>
DESC SMD No. 5962-86063
GENERAL DESCRIPTION
The WS57C256F is a High Performance 32K x 8 UV Erasable EPROM. It is manufactured using an advanced
CMOS process technology enabling it to operate at speeds as fast as 35 ns Address Access Time (t
ACC
) and 35 ns
Chip Enable Time (t
CE
). It was designed utilizing WSI's patented self-aligned split gate EPROM cell, resulting in a
low power device with a very cost effective die size. The low standby power capability of this 256 K product (200 碌A(chǔ)
in a CMOS interface environment) is especially attractive.
This product, with its high speed capability, is particularly appropriate for use with today's fast DSP processors and
high-clock-rate Microprocessors. The WS57C256F's 35 ns speed enables these advanced processors to operate
without introducing any undesirable wait states. The WS57C256F is also ideal for use in modem applications, and is
recommended for use in these applications by the leading modem chip set manufacturer.
The WS57C256F is available in a variety of package types including the space saving 300 Mil DIP, the surface
mount PLDCC, and other windowed and non-windowed options. And its standard JEDEC EPROM pinouts provide
for automatic upgrade density paths for current 64K and 128K EPROM users.
MODE SELECTION
PINS
MODE
Read
Output
Disable
Standby
Program
Program
Verify
Program
Inhibit
Signature
3
CE/
PGM
VIL
X
VIH
VIL
X
VIH
VIL
VIL
OE
VIL
VIH
X
VIH
VIL
VIH
VIL
VIL
A9
X
X
X
X
X
X
A0
X
X
X
X
X
X
VPP VCC OUTPUTS
PIN CONFIGURATION
TOP VIEW
Chip Carrier
A
7
A
12
V
PP
NC
V
CC
A
14
A
13
CERDIP
V
PP
A
12
A
7
A
6
A
5
A
4
A
3
A
2
A
1
A
0
O
0
O
1
O
2
GND
1
2
3
4
5
6
7
8
9
10
11
12
13
14
28
27
26
25
24
23
22
21
20
19
18
17
16
15
V
CC
A14
A13
A8
A9
A11
OE
A10
CE/PGM
O
7
O
6
O
5
O
4
O
3
VCC VCC
VCC VCC
VCC VCC
VPP
2
VCC
VPP
2
VCC
VPP
2
VCC
DOUT
High Z
High Z
DIN
DOUT
High Z
23 H
4
EO H
5
A
6
A
5
A
4
A
3
A
2
A
1
A
0
NC
O
0
VH
2
VIL VCC VCC
VH
2
VIH VCC VCC
4 3 2
32 31 30
1
5
29
6
28
7
27
8
26
9
25
10
24
11
23
12
22
13
21
14 15 16 17 18 19 20
O
1
O
2
GND
A
8
A
9
A
11
NC
OE
A
10
CE/PGM
O
7
O
6
NC O
3
O
4
O
5
NOTES:
1. X can be V
IL
or V
IH
.
2. V
IH
= V
PP
= 12.75 鹵 0.25 V.
3. A1 鈥?A8, A10 鈥?A14 = V
IL
.
4. Manufacturer Signature.
5. Device Signature.
PRODUCT SELECTION GUIDE
PARAMETER
Address Access Time (Max)
Output Enable Time (Max)
WS57C256F-35
35 ns
15 ns
WS57C256F-45
45 ns
20 ns
WS57C256F-55
55 ns
25 ns
WS57C256F-70
70 ns
30 ns
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