User Manual
AT27C256R
7
Notes: 1. V
CC
must be applied simultaneously or before V
PP
and removed simultaneously or after V
PP
..
2. This parameter is only sampled and is not 100% tested. Output Float is defined as the point where data is no longer driven—
see timing diagram.
3. Program Pulse width tolerance is 100
µsec
±
5%.
AC Programming Characteristics
T
A
= 25
±
5°C, V
CC
= 6.5
±
0.25V, V
PP
= 13.0
±
0.25V
Symbol Parameter Test Conditions
(1)
Limits
UnitsMin Max
t
AS
Address Setup Time
Input Rise and Fall Times
(10% to 90%) 20ns
Input Pulse Levels
0.45V to 2.4V
Input Timing Reference Level
0.8V to 2.0V
Output Timing Reference Level
0.8V to 2.0V
2
µ
s
t
OES
OE Setup Time 2
µ
s
t
DS
Data Setup Time 2
µ
s
t
AH
Address Hold Time 0
µ
s
t
DH
Data Hold Time 2
µ
s
t
DFP
OE High to
Output Float Delay
(2)
0 130 ns
t
VPS
V
PP
Setup Time 2
µ
s
t
VCS
V
CC
Setup Time 2
µ
s
t
PW
CE Program Pulse Width
(3)
95 105
µ
s
t
OE
Data Valid from OE
(2)
150 ns
t
PRT
V
PP
Pulse Rise Time
During Programming
50 ns
Atmel’s 27C256R Integrated Product Identification Code
Codes
Pins
Hex
DataA0 O7 O6 O5 O4 O3 O2 O1 O0
Manufacturer 000011110 1E
Device Type 1100011008C