
Features
•
Fast Read Access Time - 70 ns
•
Low Power CMOS Operation
–100 µA max. Standby
– 30 mA max. Active at 5 MHz
•
JEDEC Standard Packages
– 32-Lead 600-mil PDIP
– 32-Lead 450-mil SOIC (SOP)
– 32-Lead PLCC
– 32-Lead TSOP
•
5V ± 10% Supply
•
High Reliability CMOS Technology
– 2000V ESD Protection
– 200 mA Latchup Immunity
•
Rapid™ Programming Algorithm - 100 µs/byte (typical)
•
CMOS and TTL Compatible Inputs and Outputs
•
Integrated Product Identification Code
•
Commercial and Industrial Temperature Ranges
4-Megabit
(512K x 8)
OTP EPROM
Description
The AT27C040 chip is a lo w-power, high-p erformance, 4,194,304-b it one-time pro grammable read only memory (OTP EPRO M) organized as 512K by 8 bits . The
AT27C040 requires onl y one 5V power suppl y in normal read mode op eration. Any
byte can be accessed in less than 70 ns, eliminating the need for speed reducing
WAIT states on high-performance microprocessor systems.
Pin Configurations
Pin Name Function
A0 - A18 Addresses
O0 - O7 Outputs
CE
OE
PDIP, SOIC Top View
VPP
A16
A15
A12
A7
A6
A5
A4
A3
A2
A1
A0
O0
O1
O2
GND
Chip Enable
Output Enable
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
32
31
30
29
28
27
26
25
24
23
22
21
20
19
18
17
A11
A9
A8
A13
A14
A17
A18
VCC
VPP
A16
A15
A12
A7
A6
A5
A4
VCC
A18
A17
A14
A13
A8
A9
A11
OE
A10
CE
07
06
05
04
03
TSOP Top View
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
PLCC Top View
A12
432
5
A7
6
A6
7
A5
8
A4
9
A3
10
A2
11
A1
12
A0
13
O0
14151617181920
01
A15
02
A16
GND
VPP
VCC
1
323130
030405
A18
A17
29
28
27
26
25
24
23
22
21
06
A14
A13
A8
A9
A11
OE
A10
CE
07
(continued)
OE
32
A10
31
CE
30
07
29
06
28
05
27
04
26
03
25
GND
24
02
23
01
22
O0
21
A0
20
A1
19
A2
18
A3
17
AT27C040
Rev. 0189E–07/97
1

Atmel’s scaled CMOS tec hnology provides low acti ve
power cons umption, and fast pr ogrammi ng. Power consumption is typically 8 mA in active mode and less than
10 µA in standby mode.
The AT27C040 is available in a choice of industry standard
JEDEC-approved one-tim e programmable (OTP) plastic
PDIP, PLCC, SOIC (SOP), and TSO P packages. The
device features two-line control (CE
contention in high-speed systems.
Atmel’s AT27C040 has addition al features to ensure hig h
quality and efficient production use. The Rapid
ming Algori thm reduc es the time require d to prog ram the
part and guarantees reliable programming. Programming
time is typically only 100 µs/byte. The Integrated Product
Identification Code electronica lly identifi es the devic e and
manufacturer. This feature is used by industry standard
programming equi pmen t to se lect the prop er progr ammi ng
algorithms and voltages.
, OE) to eliminate bus
™
Program-
Block Diagram
Switching Considerations
Switching between active and standby conditions via the
Chip Enable pin may produ ce tra ns ien t vo ltag e ex cu rs i ons .
Unless accommodated by the system design, these transients may exceed data sheet limits, resulting in device
non-conforman ce. At a mini mum, 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
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
terminals. This capacitor should be positioned as close as
possible to the point where the power supply is connected
to the array.
and Ground terminals of the device, as
CC
and Ground
CC
2
AT27C040

Operating Modes
AT27C040
Mode/Pin CE OE Ai V
Read V
IL
Output Disable X V
Standby V
Rapid Program
(2)
IH
V
IL
PGM Verify X V
PGM Inhibit V
Product Identification
(4)
IH
V
IL
V
IL
IH
Ai X
XXHigh Z
X X X High Z
V
IH
IL
V
IH
V
IL
Ai V
Ai V
XVPPHigh Z
A9 = V
(3)
H
A0 = VIH or VIL
A1 - A18 = V
IL
Notes: 1. X can be VIL or VIH.
2. Refer to Programming Characteristics
3. VH = 12.0 ± 0.5V.
4. Two identifier bytes ma y be se lected. All Ai inputs are held lo w (V
) to select the Manufacturer’s Identificaton byte and high (VIH) to select the Device Code byte.
(V
IL
), except A9 which is set to VH and A0 which is toggled low
IL
Absolute Maximum Ratings*
Temperature Under Bias................................-55°C to +125°C
Storage Temperature..................................... -65°C to +150°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
*NOTICE: Stresses beyond those listed under “Absolute
Maximum Ratings” may cause permanent damage to the de vic e. T his is a stres s r ating o nly an d
functional opera tion 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 re li abi li ty.
PP
(1)
PP
PP
Outputs
D
OUT
D
IN
D
OUT
X Identification Code
V
Supply Voltage with
PP
Respect to Ground ..........................................-2.0V to +14.0V
3

DC and AC Operating Conditions for Read Operation
AT27C040-70 AT27C040-90 AT27C040-12 AT27C040-15
Operating
Temperature (Case)
V
Power Supply 5V ± 10% 5V ± 10% 5V ± 10% 5V ± 10%
CC
Com. 0°C - 70°C 0°C - 70°C 0°C - 70°C 0°C - 70°C
Ind. -40°C - 85°C -40°C - 85°C -40°C - 85°C -40°C - 85°C
DC and Operating Characteristics for Read Operation
Symbol Paramter Condition Min Max Units
I
I
I
I
I
V
V
V
V
LI
LO
PP1
SB
CC
IL
IH
OL
OH
(2)
Input Load Current VIN = 0V to V
Output Leakage Current V
(1)
V
Read/Standby Current VPP = V
PP
(1)
V
Standby Current
CC1
= 0V to V
OUT
I
(CMOS), CE = VCC ± 0.3V 100 µA
SB1
I
(TTL), CE = 2.0 to V
SB2
VCC Active Current f = 5 MHz, I
CC
CC
CC
= 0 mA, CE = V
OUT
+ 0.5V 1 mA
CC
IL
Input Low Voltage -0.6 0.8 V
Input High Vo ltage 2.0 V
Output Low Voltage IOL = 2.1 mA 0.4 V
Output High Voltage IOH = -400 µA2.4V
Notes: 1. VCC must be applied simultaneously or before VPP, and removed simultaneously or after VPP.
2. VPP may be connected directly to VCC, except during programming. The supply current would then be the sum of ICC and IPP.
AC Characteristics for Read Operation
AT27C040
-70 -90 -12 -15
Symbol Parameter Condition
= OE
t
t
t
t
ACC
CE
OE
DF
(3)
(2)
(2)(3)
(4)(5)
Address to Output Delay
CE to Output Delay OE = V
OE to Output Delay CE = V
OE or CE High to Output Float, whichever
occurred first
CE
= V
IL
IL
Min Max Min Max Min Max Min Max
IL
70 90 120 150 ns
70 90 120 150 ns
30 35 35 40 ns
20 20 30 30 ns
±1 µA
±5 µA
10 µA
30 mA
+ 0.5 V
CC
Units
t
OH
Output Hold from Address, CE or OE,
whichever occurred f irst
Notes: 1. 2, 3, 4, 5 - see AC Waveforms for Read Operation
4
AT27C040
0000ns