AT27LV256A
256K (32K x 8)
Low Voltage
OTP
CMOS EPROM
Features
Fast Read Access Time - 70 ns
Dual Voltage Range Operation
Low Voltage Power Supply Range, 3.0V to 3.6V
or Standard 5V
10% Supply Range
Pin Compatible with JEDEC Standard AT27C256
Low Power CMOS Operation
20
A max. (less than 1
A typical) Standby for V
CC
= 3.6V
29 mW max. Active at 5 MHz for V
CC
= 3.6V
JEDEC Standard Packages
32-Lead PLCC
28-Lead 330-mil SOIC
28-Lead TSOP
High Reliability CMOS Technology
2,000V ESD Protection
200 mA Latchup Immunity
Rapid
TM
Programming Algorithm - 100
s/byte (typical)
CMOS and TTL Compatible Inputs and Outputs
JEDEC Standard for LVTTL
Integrated Product Identification Code
Commercial and Industrial Temperature Ranges
Description
The AT27LV256A is a high performance, low power, low voltage 262,144 bit one-time
programmable read only memory (OTP EPROM) organized as 32K by 8 bits. It re-
quires only one supply in the range of 3.0V to 3.6V in normal read mode operation,
making it ideal for fast, portable systems using battery power.
Atmel's innovative design techniques provide fast speeds that rival 5V parts while
keeping the low power consumption of a 3.3V supply. At V
CC
= 3.0V, any byte can be
accessed in less than 70 ns. With a typical power dissipation of only 18 mW at 5 MHz
and V
CC
= 3.3V, the AT27LV256A consumes less than one fifth the power of a stand-
ard 5V EPROM.
(continued)
Pin Configurations
Pin Name
Function
A0 - A14
Addresses
O0 - O7
Outputs
CE
Chip Enable
OE
Output Enable
NC
No Connect
0547A
SOIC Top View
Note:PLCC Package Pins 1 and 17
are DON'T CONNECT.
PLCC Top View
TSOP Top View
Type 1
AT27LV256A
3-75
Standby mode supply current is typically less than 1
A at
3.3V.
The AT27LV256A is available in industry standard
JEDEC-approved one-time programmable (OTP) plastic
PLCC, SOIC and TSOP packages . All devices feature
two-line control (CE, OE) to give designers the flexibility to
prevent bus contention.
The AT27LV256A operating with V
CC
at 3.0V produces
TTL level outputs that are compatible with standard TTL
logic devices operating at V
CC
= 5.0V. The device is also
capable of standard 5-volt operation making it ideally
suited for dual supply range systems or card products that
are pluggable in both 3-volt and 5-volt hosts.
Atmel's AT27LV256A has additional features to ensure
high quality and efficient production use. The Rapid
TM
Pro-
gramming Algorithm reduces the time required to program
the part and guarantees reliable programming. Program-
ming time is typically only 100
s/byte. The Integrated
Product Identification Code electronically identifies the de-
vice and manufacturer. This feature is used by industry
standard programming equipment to select the proper
programming algorithms and voltages. The AT27LV256A
programs exactly the same way as a standard 5V
AT27C256R and uses the same programming equipment.
Description (Continued)
Switching between active and standby conditions via the
Chip Enable pin may produce transient voltage excur-
sions. Unless accommodated by the system design, these
transients may exceed data sheet limits, resulting in de-
vice non-conformance. At a minimum, a 0.1
F high fre-
quency, low inherent inductance, ceramic capacitor
should be utilized for each device. This capacitor should
be connected between the V
CC
and Ground terminals of
the device, as close to the device as possible. Additionally,
to stabilize the supply voltage level on printed circuit
boards with large EPROM arrays, a 4.7
F bulk electrolytic
capacitor should be utilized, again connected between the
V
CC
and Ground terminals. This capacitor should be posi-
tioned as close as possible to the point where the power
supply is connected to the array.
System Considerations
3-76
AT27LV256A
Block Diagram
Temperature Under Bias .................. -40C to +85C
Storage Temperature...................... -65C to +125C
Voltage on Any Pin with
Respect to Ground......................... -2.0V to +7.0V
(1)
Voltage on A9 with
Respect to Ground ...................... -2.0V to +14.0V
(1)
V
PP
Supply Voltage with
Respect to Ground....................... -2.0V to +14.0V
(1)
*NOTICE: Stresses beyond those listed under "Absolute Maxi-
mum Ratings" may cause permanent damage to the device.
This is a stress rating only and functional operation of the
device at these or any other conditions beyond those indi-
cated in the operational sections of this specification is not
implied. Exposure to absolute maximum rating conditions
for extended periods may affect device reliability.
Note: 1. Minimum voltage is -0.6V dc which may undershoot
to -2.0V for pulses of less than 20 ns. Maximum out-
put pin voltage is V
CC
+ 0.75V dc which may be ex-
ceeded if certain precautions are observed (consult
application notes) and which may overshoot to +7.0
volts for pulses of less than 20 ns.
Absolute Maximum Ratings*
Operating Modes
Mode \ Pin
CE
OE
Ai
V
PP
V
CC
Outputs
Read
(2)
V
IL
V
IL
Ai
V
CC
V
CC
(2)
D
OUT
Output Disable
(2)
V
IL
V
IH
X
(1)
V
CC
V
CC
(2)
High Z
Standby
(2)
V
IH
X
(1)
X
(1)
V
CC
V
CC
(2)
High Z
Rapid Program
(3)
V
IL
V
IH
Ai
V
PP
V
CC
(3)
D
IN
PGM Verify
(3)
X
(1)
V
IL
Ai
V
PP
V
CC
(3)
D
OUT
Optional PGM Verify
(3)
V
IL
V
IL
Ai
V
CC
V
CC
(3)
D
OUT
PGM Inhibit
(3)
V
IH
V
IH
X
(1)
V
PP
V
CC
(3)
High Z
Product Identification
(3, 5)
V
IL
V
IL
A9 = V
H
(4)
A0 = V
IH
or V
IL
A1 - A14 = V
IL
V
CC
V
CC
(3)
Identification
Code
Notes: 1. X can be V
IL
or V
IH
.
2. Read, output disable, and standby modes require,
3.0V
V
CC
3.6V, or 4.5V
V
CC
5.5V.
3. Refer to Programming Characteristics. Programming
modes require V
CC
= 6.5V.
4. V
H
= 12.0
0.5V.
5. Two identifier bytes may be selected. All Ai inputs
are held low (V
IL
), except A9 which is set to V
H
and A0
which is toggled low (V
IL
) to select the Manufacturer's Identi-
fication byte and high (V
IH
) to select the Device Code byte.
AT27LV256A
3-77
DC and AC Operating Conditions for Read Operation
AT27LV256A
-70
-90
-12
-15
Operating Temperature
(Case)
Com.
0C - 70C
0C - 70C
0C - 70C
0C - 70C
Ind.
-40C - 85C
-40C - 85C
-40C - 85C
-40C - 85C
V
CC
Power Supply
3.0V to 3.6V
3.0V to 3.6V
3.0V to 3.6V
3.0V to 3.6V
5V
10%
5V
10%
5V
10%
5V
10%
DC and Operating Characteristics for Read Operation
Symbol
Parameter
Condition
Min
Max
Units
V
CC
= 3.0V to 3.6V
I
LI
Input Load Current
V
IN
= 0V to V
CC
1
A
I
LO
Output Leakage Current
V
OUT
= 0V to V
CC
5
A
I
PP1
(
2
)
V
PP
(
1
)
Read/Standby Current
V
PP
= V
CC
10
A
I
SB
V
CC
(
1
)
Standby Current
I
SB1
(CMOS), CE = V
CC
0.3V
20
A
I
SB2
(TTL), CE = 2.0 to V
CC
+ 0.5V
100
A
I
CC
V
CC
Active Current
f = 5 MHz, I
OUT
= 0 mA,
CE = V
IL
8
mA
V
IL
Input Low Voltage
-0.6
0.8
V
V
IH
Input High Voltage
2.0
V
CC
+ 0 .5
V
V
OL
Output Low Voltage
I
OL
= 2.0 mA
0.4
V
V
OH
Output High Voltage
I
OH
= -2.0
mA
2.4
V
V
CC
= 4.5V to 5.5V
I
LI
Input Load Current
V
IN
= 0V to V
CC
1
A
I
LO
Output Leakage Current
V
OUT
= 0V to V
CC
5
A
I
PP1
(
2
)
V
PP
(
1
)
Read/Standby Current
V
PP
= V
CC
10
A
I
SB
V
CC
(1)
Standby Current
I
SB1
(CMOS), CE = V
CC
0.3V
100
A
I
SB2
(TTL), CE = 2.0 to V
CC
+ 0.5V
1
mA
I
CC
V
CC
Active Current
f = 5 MHz, I
OUT
= 0 mA,
CE = V
IL
20
mA
V
IL
Input Low Voltage
-0.6
0.8
V
V
IH
Input High Voltage
2.0
V
CC
+ 0.5
V
V
OL
Output Low Voltage
I
OL
= 2.1 mA
0.4
V
V
OH
Output High Voltage
I
OH
= -400
A
2.4
V
Notes: 1. V
CC
must be applied simultaneously with or before
V
PP
, and removed simultaneously with or after
V
PP
.
2. V
PP
may be connected directly to V
CC
, except during
programming. The supply current would then be the sum
of I
CC
and I
PP
.
3-78
AT27LV256A
AC Characteristics for Read Operation
(V
CC
= 3.0V to 3.6V and 4.5V to 5.5V)
AT27LV256A
-70
-90
-12
-15
Symbol
Parameter
Condition
Min
Max
Min
Max
Min
Max
Min
Max
Units
t
ACC
(
3
)
Address to Output Delay
CE = OE = V
IL
70
90
120
150
ns
t
CE
(
2
)
CE to Output Delay
OE = V
IL
70
90
120
150
ns
t
OE
(2, 3)
OE to Output Delay
CE = V
IL
50
50
50
60
ns
t
DF
(4, 5)
OE or CE High to Output Float,
whichever occurred first
40
40
40
50
ns
t
OH
Output Hold from Address, CE or
OE, whichever occurred first
0
0
0
0
ns
Notes:
2, 3, 4, 5. - see AC Waveforms for Read Operation.
AC Waveforms for Read Operation
(1)
Notes: 1. Timing measurement references are 0.8V and 2.0V.
Input AC drive levels are 0.45V and 2.4V, unless
otherwise specified.
2. OE may be delayed up to t
CE
- t
OE
after the falling edge
of CE without impact on t
CE
.
3. OE may be delayed up to t
ACC
- t
OE
after the
address is valid without impact on t
ACC
.
4. This parameter is only sampled and is not 100% tested.
5. Output float is defined as the point when data is no longer
driven.
AT27LV256A
3-79
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