X28HC256 Datasheet, PDF (2/24 Pages) Xicor Inc. – 5 Volt, Byte Alterable E2PROM

X28HC256
PIN DESCRIPTIONS
Addresses (A₀–A₁₄)
The Address inputs select an 8-bit memory location
during a read or write operation.
Chip Enable (CE)
The Chip Enable input must be LOW to enable all read/
write operations. When CE is HIGH, power consumption
is reduced.
Output Enable (OE)
The Output Enable input controls the data output buffers
and is used to initiate read operations.
Data In/Data Out (I/O₀–I/O₇)
Data is written to or read from the X28HC256 through
the I/O pins.
Write Enable (WE)
The Write Enable input controls the writing of data to the
X28HC256.
FUNCTIONAL DIAGRAM
PIN NAMES
Symbol
A0–A14
I/O0–I/O7
WE
CE
OE
V_CC
VSS
NC
Description
Address Inputs
Data Input/Output
Write Enable
Chip Enable
Output Enable
+5V
Ground
No Connect
3859 PGM T01
PIN CONFIGURATION
PGA
I/O1 I/O2 I/O3 I/O5 I/O6
12
13
15
17
18
I/O0 A0
VSS I/O4 I/O7
11
10
14
16
19
A1
A2
9
8
A3
A4
7
6
CE A10
20
21
OE A11
22
23
A5
A12 VCC A9
A8
5
2
28
24
25
A6
A7
A14 WE A13
4
3
1
27
26
X28HC256
(BOTTOM VIEW)
3859 FHD F04
A0–A14
ADDRESS
INPUTS
X BUFFERS
LATCHES AND
DECODER
Y BUFFERS
LATCHES AND
DECODER
CE
OE
WE
VCC
VSS
CONTROL
LOGIC AND
TIMING
256K-BIT
E2PROM
ARRAY
I/O BUFFERS
AND LATCHES
I/O0–I/O7
DATA INPUTS/OUTPUTS
3859 FHD F01
3859 FHD F01
2