Features
•
Fast Read Access Time - 90 ns
•
Dual Voltage Range Operation
•
•
•
Low Voltage Power Supply Range, 3.0V to 3.6V
or Standard 5V
±
10% Supply Range
Compatible with JEDEC Standard AT27C020
Low Power CMOS Operation
20
µA
max. (less than 1
µA
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
32-Lead TSOP (8 X 20 mm)
32-Lead VSOP (8 x 14 mm)
High Reliability CMOS Technology
2,000V ESD Protection
200 mA Latchup Immunity
Rapid
™
Programming Algorithm - 100
µs/byte
(typical)
Two-Line Control
CMOS and TTL Compatible Inputs and Outputs
JEDEC Standard for LVTTL
Integrated Product Identification Code
Commercial and Industrial Temperature Ranges
•
•
•
•
•
•
2 Megabit
(256K x 8)
Low Voltage
OTP EPROM
AT27LV020A
Description
The AT27LV020A is a high performance, low power, low voltage 2,097,152 bit one-
time programmable read only memory (OTP EPROM) organized as 256K by 8 bits. It
requires only one supply in the range of 3.0 to 3.6V in normal read mode operation,
making it ideal for fast, portable systems using battery power.
Pin Configurations
Pin Name
A0 - A17
O0 - O7
CE
OE
PGM
Function
Addresses
Outputs
Chip Enable
Output Enable
Program Strobe
PLCC, Top View
TSOP, VSOP Top View
Type 1
0549B-A–9/97
1
Atmel's innovative design techniques provide fast speeds
that rival 5V parts while keeping the low power consump-
tion of a 3V supply. At V
CC
= 3.0V, any byte can be
accessed in less than 90 ns. With a typical power dissipa-
tion of only 18 mW at 5 MHz and V
C C
= 3.3V, the
AT27LV020A consumes less than one fifth the power of a
standard 5V EPROM. Standby mode supply current is typi-
cally less than 1
µA
at 3.3V.
The AT27LV020A is available in industry standard JEDEC
approved one-time programmable (OTP) plastic PLCC,
TSOP and VSOP packages. All devices feature two-line
control (CE, OE) to give designers the flexibility to prevent
bus contention.
The AT27LV020A 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 AT27LV020A has additional features to ensure
high quality and efficient production use. The Rapid
™
Pro-
gramming Algorithm reduces the time required to program
the part and guarantees reliable programming. Program-
ming time is typically only 100
µs/byte.
The Integrated
Product Identification Code electronically identifies the
device and manufacturer. This feature is used by industry
standard programming equipment to select the proper pro-
gramming algorithms and voltages. The AT27LV020A pro-
grams exactly the same way as a standard 5V AT27C020
and uses the same programming equipment.
System Considerations
Switching between active and standby conditions via the
Chip Enable pin may produce transient voltage excursions.
Unless accommodated by the system design, these tran-
sients may exceed data sheet limits, resulting in device
non-conformance. At a minimum, a 0.1
µF
high frequency,
low inherent inductance, ceramic capacitor should be uti-
lized 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
µF
bulk electrolytic capacitor should
be utilized, again connected between the V
CC
and Ground
terminals. This capacitor should be positioned as close as
possible to the point where the power supply is connected
to the array.
2
AT27LV020A
AT27LV020A
Block Diagram
Absolute Maximum Ratings*
Temperature Under Bias .................................. -40°C to +85°C
Storage Temperature ..................................... -65°C to +125°C
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 indicated in the
operational sections of this specification is not implied. Expo-
sure to absolute maximum rating conditions for extended peri-
ods 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
exceeded if certain precautions are observed (con-
sult application notes) and which may overshoot to
+7.0 volts for pulses of less than 20 ns.
Operating Modes
Mode \ Pin
Read
(2)
Output Disable
(2)
Standby
(2)
Rapid Program
(3)
PGM Verify
(3)
PGM Inhibit
(3)
Product Identification
(3, 5)
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.
CE
V
IL
X
V
IH
V
IL
V
IL
V
IH
V
IL
OE
V
IL
V
IH
X
V
IH
V
IL
X
V
IL
PGM
X
(1)
X
X
V
IL
V
IH
X
X
Ai
Ai
X
X
Ai
Ai
X
V
PP
X
X
X
V
PP
V
PP
V
PP
V
CC
V
CC (2)
V
CC (2)
V
CC (2)
V
CC (3)
V
CC (3)
V
CC (3)
Outputs
D
OUT
High Z
High Z
D
IN
D
OUT
High Z
A9 = V
H (4)
A0 = V
IH
or V
IL
X
V
CC (3)
Identification Code
A1 - A17 = V
IL
5. Two identifier bytes may be selected. All Ai inputs are
held low (V
IL
), except A9 which is set to VH and A0
which is toggled low (V
IL
) to select the Manufacturer’s
Identification byte and high (V
IH
) to select the Device
Code byte.
3
DC and AC Operating Conditions for Read Operation
AT27LV020A
-90
Com.
Operating Temperature (Case)
Ind.
V
CC
Power Supply
-40°C - 85°C
3.0V to 3.6V
5V
±
10%
-40°C - 85°C
3.0V to 3.6V
5V
±
10%
-40°C - 85°C
3.0V to 3.6V
5V
±
10%
0°C - 70°C
-12
0°C - 70°C
-15
0°C - 70°C
DC and Operating Characteristics for Read Operation
Symbol
Parameter
Condition
Min
Max
±1
±5
10
20
100
8
-0.6
2.0
I
OL
= 2.0 mA
I
OH
= -2.0 mA
V
IN
= 0V to V
CC
V
OUT
= 0V to V
CC
V
PP
= V
CC
I
SB1
(CMOS), CE = V
CC
±
0.3V
I
SB2
(TTL), CE = 2.0 to V
CC
+ 0.5V
I
CC
V
IL
V
IH
V
OL
V
OH
V
CC
Active Current
Input Low Voltage
Input High Voltage
Output Low Voltage
Output High Voltage
I
OL
= 2.1 mA
I
OH
= -400
µA
2.4
f = 5 MHz, I
OUT
= 0 mA,
CE = V
IL
-0.6
2.0
2.4
±1
±5
10
100
1
25
0.8
V
CC
+ 0.5
0.4
0.8
V
CC
+ 0 .5
0.4
Units
µA
µA
µA
µA
µA
mA
V
V
V
V
µA
µA
µA
µA
mA
mA
V
V
V
V
V
CC
= 3.0V to 3.6V
I
LI
I
LO
I
PP1 (2)
I
SB
Input Load Current
Output Leakage Current
Read/Standby Current
V
CC (1)
Standby Current
V
IN
= 0V to V
CC
V
OUT
= 0V to V
CC
V
PP
= V
CC
I
SB1
(CMOS), CE = V
CC
±
0.3V
I
SB2
(TTL), CE = 2.0 to V
CC
+ 0.5V
I
CC
V
IL
V
IH
V
OL
V
OH
I
LI
I
LO
I
PP1 (2)
I
SB
V
CC
Active Current
Input Low Voltage
Input High Voltage
Output Low Voltage
Output High Voltage
f = 5 MHz, I
OUT
= 0 mA,
CE = V
IL
V
CC
= 4.5V to 5.5V
Input Load Current
Output Leakage Current
Read/Standby Current
V
CC (1)
Standby Current
4
AT27LV020A
AT27LV020A
AC Characteristics for Read Operation
(V
CC
= 3.0V to 3.6V and 4.5V to 5.5V)
AT27LV020A
-90
Symbol
t
ACC (3)
t
CE (2)
t
OE (2, 3)
t
DF (4, 5)
t
OH
Parameter
Address to Output Delay
CE to Output Delay
OE to Output Delay
OE or CE High to Output Float,
whichever occurred first
Output Hold from Address, CE or OE,
whichever occurred first
0
Condition
CE = OE = V
IL
OE = V
IL
CE = V
IL
Min
Max
Min
-12
Max
Min
-15
Max
Units
ns
ns
ns
ns
ns
90
90
50
40
0
120
120
50
40
0
150
150
60
50
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 oth-
erwise specififed.
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.
5
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