X28VC256
256K
X28VC256
5 Volt, Byte Alterable E2PROM
DESCRIPTION
32K x 8 Bit
FEATURES
• Access Time: 45ns
• Simple Byte and Page Write
—Single 5V Supply
The X28VC256 is a second generation high perfor-
mance CMOS 32K x 8 E PROM. It is fabricated with
Xicor’s proprietary, textured poly floating gate tech-
nology, providing a highly reliable 5 Volt only nonvolatile
memory.
2
—No External High Voltages or V Control
PP
Circuits
—Self-Timed
The X28VC256 supports a 128-byte page write opera-
tion, effectively providing a 24µs/byte write cycle and
enabling the entire memory to be typically rewritten in
less than 0.8 seconds. The X28VC256 also features
DATA Polling and Toggle Bit Polling, two methods of
providing early end of write detection. The X28VC256
also supports the JEDEC standard Software Data Pro-
tection feature for protecting against inadvertent writes
during power-up and power-down.
—No Erase Before Write
—No Complex Programming Algorithms
—No Overerase Problem
• Low Power CMOS:
—Active: 80mA
—Standby: 10mA
• Software Data Protection
—Protects Data Against System Level
Inadvertent Writes
• High Speed Page Write Capability
Endurance for the X28VC256 is specified as a minimum
100,000 write cycles per byte and an inherent data
retention of 100 years.
™
• Highly Reliable Direct Write Cell
—Endurance: 100,000 Write Cycles
—Data Retention: 100 Years
• Early End of Write Detection
—DATA Polling
—Toggle Bit Polling
PIN CONFIGURATION
PLASTIC DIP
CERDIP
FLAT PACK
LCC
PLCC
SOIC
TSOP
A14
1
2
3
4
5
6
7
8
9
28
27
26
25
24
23
22
21
20
19
18
17
16
15
V
CC
4
3
2
1
32 31 30
29
A
WE
A
A
A
I/O
I/O
I/O
1
2
3
4
5
6
7
8
32
31
30
29
28
27
26
25
24
23
22
21
20
19
18
17
A
A
A
A
A
A
A
NC
V
NC
WE
12
2
1
0
0
1
2
3
4
5
6
7
12
14
A
7
A
6
A
5
A
4
A
3
A
2
A
1
A
0
A
A
A
A
A
A
A
A
5
6
7
8
9
A
A
A
13
6
5
4
3
2
1
0
8
A
8
A
9
28
27
26
25
24
23
22
21
9
11
A
NC
OE
A
11
NC
X28VC256
OE
V
SS
NC
X28VC256
X28VC256
9
CC
A
10
11
12
13
10
10
I/O
10
11
12
13
14
15
16
3
4
5
6
7
CE
CE
I/O
I/O
I/O
I/O
I/O
A
A
A
A
13
8
9
10
11
12
13
14
I/O
7
I/O
6
I/O
5
I/0
4
NC
I/O
7
I/O
0
I/O
1
I/O
2
I/O
0
6
14 15 16 17 18 19 20
CE
11
A
OE
10
V
I/O
3
SS
3869 FHD F03
3869 ILL F22
3869 FHD F02
©Xicor, Inc. 1991, 1995 Patents Pending
3869-2.6 4/2/96 T4/C4/D0 NS
Characteristics subject to change without notice
1