256K (32K x 8)
Low Voltage
OTP
CMOS EPROM
Features
Fast Read Access Ti me - 70 ns
•
Dual Voltage Range Operation
•
Low Voltage Power Supply Ran ge , 3. 0V to 3. 6V
or Standard 5V ± 10% Supply Range
Pin Compatible with JEDEC Standard AT27C256
•
Low Power CMOS Operation
•
20 µA max. (less than 1 µA typical) Standby for VCC = 3.6V
29 mW max. Active at 5 MHz for VCC = 3.6V
JEDEC Standard Packages
•
32-Lead PLCC
28-Lead 330-mil SOIC
28-Lead TSOP
High Reliabili ty C MOS Te ch nology
•
2,000V ESD Protection
200 mA Latchup Imm un ity
RapidProgramming Algo rith m - 100 µs/byte (typical )
•
CMOS and TTL Compatible Inputs and Outputs
•
JEDEC Standard for LVTTL
Integrated Produc t Ide nti fication 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 requires 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
accessed in less than 70 ns. With a typical power dissipation of only 18 mW at 5 MHz
and V
ard 5V EPROM.
Pin Configurations
Pin Name Function
A0 - A14 Addresses
O0 - O7 Outputs
CE Chip Enable
OE Output Enable
NC No Connect
= 3.3V, the AT27LV256A consumes less than one fifth the power of a stand-
CC
SOIC Top View
PLCC Top View
= 3.0V, any byte can be
CC
(continued)
AT27LV256A
Note:PLCC Package Pins 1 and 17
are DON’T CONNECT.
TSOP Top View
Type 1
3-75
Description (Continued)
Standby mode supply current is typically less than 1 µA 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 (
prevent bus contention.
The AT27LV256A operating with V
TTL level outputs that are compatible with standard TTL
logic devices operating at V
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
gramming Algorithm reduces the time required to program
the part and guarantees reliable programming. Programming time i s 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
programming algorithms and voltages. The AT27LV256A
programs exactly the same way as a standard 5V
AT27C256R and uses the same programming equipment.
CE, OE) to give designers the flexibility to
at 3.0V produces
CC
= 5.0V. The device is also
CC
Pro-
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
transients 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 utilized for each device. This capacitor should
be connected between the V
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
and Ground terminals. This capacitor should be posi-
V
CC
tioned as close as possible to the point where the power
supply is connected to the array.
and Ground terminals of
CC
3-76 AT27LV256A
AT27LV256A
Block Diagram
Absolute Maximum Ra ti ngs *
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
Voltage on A9 with
Respect to Ground ......................-2.0V to +14.0V
VPP Supply Voltage with
Respect to Ground.......................-2.0V to +14.0V
*NOTICE: Stresses beyond those listed unde r “Absolu te Maxi-
mum Ratings” may cause permanent da ma ge to th e de vice .
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. 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 output pin voltage is V
ceeded if certain precautions are observed (consult
application notes) and which may overshoot to +7.0
volts for pulses of less than 20 ns.
+ 0.75V dc which may be ex-
CC
(1)
(1)
(1)
Operating Modes
Mode \ Pin
(2)
Read
Output Disable
Standby
(2)
Rapid Program
PGM Verify
Optional PGM Verify
PGM Inhibit
Product Identification
Notes: 1. X can be VIL or VIH.
2. Read, output disable, and standby modes require,
3.0V ≤ VCC ≤ 3.6V, or 4.5V ≤ VCC ≤ 5.5V.
3. Refer to Programming Characteristi cs. Programming
modes require VCC = 6.5V.
(2)
(3)
(3)
(3)
(3)
(3, 5)
CE OE Ai V
V
V
V
V
X
V
V
V
IL
IL
IH
IL
(1)
IL
IH
IL
V
V
X
V
V
V
V
V
IL
IH
(1)
IH
IL
IL
IH
A0 = VIH or VIL
IL
A1 - A14 = V
Ai V
(1)
X
(1)
X
Ai V
Ai V
Ai V
(1)
X
A9 = VH
(4)
IL
4. VH = 12.0 ± 0.5V.
5. Two identi fier bytes may be selected. Al l Ai in puts
are held low (VIL), except A9 which is set to VH and A0
which is togg le d low (V
fication byte and high (V
PP
CC
V
CC
V
CC
PP
PP
CC
V
PP
V
CC
V
CC
(2)
V
CC
(2)
V
CC
(2)
V
CC
(3)
V
CC
(3)
V
CC
(3)
V
CC
(3)
V
CC
(3)
V
CC
) to select the Manufacturer’s Identi-
IL
) to select the Dev ice Code byte.
IH
Outputs
D
OUT
High Z
High Z
D
IN
D
OUT
D
OUT
High Z
Identification
Code
3-77