Features
•
Fast Read Access Time – 55 ns
•
Low Power CMOS Operation
– 100 µA Maximum Standby
– 35 mA Maximum Active at 5 MHz
JEDEC Standard Packages
– 40-lead PDIP
– 44-lead PLCC
– 40-lead VSOP
Direct Upgrade from 512-Kbit and 1-Mbit (AT27C516 and AT27C1024) EPROMs
5V
±
10% Power Supply
High Reliability CMOS Technology
– 2,000V ESD Protection
– 200 mA Latchup Immunity
Rapid Programming Algorithm – 50 µs/Word (Typical)
CMOS and TTL Compatible Inputs and Outputs
Integrated Product Identification Code
Industrial Temperature Range
•
•
•
•
2-Megabit
(128K x 16)
OTP EPROM
AT27C2048
•
•
•
•
1. Description
The AT27C2048 is a low-power, high-performance 2,097,152-bit one-time program-
mable read-only memory (OTP EPROM) organized 128K by 16 bits. It requires a
single 5V power supply in normal read mode operation. Any word can be accessed in
less than 55 ns, eliminating the need for speed-reducing WAIT states. The by-16
organization makes this part ideal for high-performance 16 and 32 bit microprocessor
systems.
In read mode, the AT27C2048 typically consumes 15 mA. Standby mode supply cur-
rent is typically less than 10 µA.
The AT27C2048 is available in industry-standard JEDEC-approved one-time pro-
grammable (OTP) plastic PDIP, PLCC, and VSOP packages. The device features
two-line control (CE, OE) to eliminate bus contention in high-speed systems.
With high density 128K word storage capability, the AT27C2048 allows firmware to be
stored reliably and to be accessed by the system without the delays of mass storage
media.
Atmel’s AT27C2048 has additional features that ensure high quality and efficient pro-
duction use. The Rapid Programming Algorithm reduces the time required to program
the part and guarantees reliable programming. Programming time is typically only
50 µs/word. 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.
0632F–EPROM–12/07
2. Pin Configurations
Pin Name
A0 - A16
O0 - O15
CE
OE
PGM
NC
DC
Note:
Function
Addresses
Outputs
Chip Enable
Output Enable
Program Strobe
No Connect
Don’t Connect
Both GND pins must be connected.
A9
A10
A11
A12
A13
A14
A15
A16
PGM
VCC
VPP
CE
O15
O14
O13
O12
O11
O10
O9
O8
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
40
39
38
37
36
35
34
33
32
31
30
29
28
27
26
25
24
23
22
21
GND
A8
A7
A6
A5
A4
A3
A2
A1
A0
OE
O0
O1
O2
O3
O4
O5
O6
O7
GND
2.2
40-lead VSOP (Type 1) Top View
2.1
40-lead PDIP Top View
VPP
CE
O15
O14
O13
O12
O11
O10
O9
O8
GND
O7
O6
O5
O4
O3
O2
O1
O0
OE
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
40
39
38
37
36
35
34
33
32
31
30
29
28
27
26
25
24
23
22
21
VCC
PGM
A16
A15
A14
A13
A12
A11
A10
A9
GND
A8
A7
A6
A5
A4
A3
A2
A1
A0
2.3
44-lead PLCC Top View
O13
O14
O15
CE
VPP
DC
VCC
PGM
A16
A15
A14
Note:
Note: PLCC package pins 1 and 23 are Don’t Connect.
2
AT27C2048
0632F–EPROM–12/07
O3
O2
O1
O0
OE
DC
A0
A1
A2
A3
A4
18
19
20
21
22
23
24
25
26
27
28
O12
O11
O10
O9
O8
GND
NC
O7
O6
O5
O4
7
8
9
10
11
12
13
14
15
16
17
6
5
4
3
2
1
44
43
42
41
40
39
38
37
36
35
34
33
32
31
30
29
A13
A12
A11
A10
A9
GND
NC
A8
A7
A6
A5
AT27C2048
3. 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
datasheet 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
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 con-
nected 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.
4. Block Diagram
VCC
GND
VPP
OE
CE
A0 - A17
ADDRESS
INPUTS
OE, CE AND
PROGRAM LOGIC
Y DECODER
X DECODER
IDENTIFICATION
DATA OUTPUTS
O0 - O15
OUTPUT
BUFFERS
Y-GATING
CELL MATRIX
5. 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
(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)
Note:
1. Maximum voltage is -0.6V DC which may undershoot to -2.0V for pulses of less than 20 ns. Maximum output pin voltage is
V
CC
+ 0.75V DC which may overshoot to +7.0V for pulses of less than 20 ns.
*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 condi-
tions beyond those indicated in the operational sec-
tions of this specification is not implied. Exposure to
absolute maximum rating conditions for extended
periods may affect device reliability.
3
0632F–EPROM–12/07
6. Operating Modes
Mode/Pin
Read
Output Disable
Standby
Rapid Program
(2)
PGM Verify
PGM Inhibit
Product Identification
(4)
Notes:
1. X can be V
IL
or V
IH
.
2. Refer to the Programming characteristics.
3. V
H
= 12.0
±
0.5V.
4. Two identifier words 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 Identification word and high (V
IH
) to select the Device Code word.
5. Standby V
CC
current (I
SB
) is specified with V
PP
= V
CC
. V
CC
> V
PP
will cause a slight increase in I
SB
.
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
A9 = V
H(3)
A0 = V
IH
or V
IL
A1 - A16 = V
IL
V
PP
X
(1)
X
X
(5)
V
PP
V
PP
V
PP
V
CC
Outputs
D
OUT
High Z
High Z
D
IN
D
OUT
High Z
Identification Code
7. DC and AC Operating Conditions for Read Operation
AT27C2048
-55
Industrial Operating Temperature (Case)
V
CC
Power Supply
-40° C - 85° C
5V
±
10%
-90
-40° C - 85° C
5V
±
10%
8. DC and Operating Characteristics for Read Operation
Symbol
I
LI
I
LO
I
PP1(2)
Parameter
Input Load Current
Output Leakage Current
V
PP(1)
Read/Standby Current
Condition
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
f = 5 MHz, I
OUT
= 0 mA, CE = V
IL
-0.6
2.0
I
OL
= 2.1 mA
I
OH
= -400 µA
2.4
Min
Max
±
1
±
5
10
100
1
35
0.8
V
CC
+ 0.5
0.4
Units
µA
µA
µA
µA
mA
mA
V
V
V
V
I
SB
V
CC(1)
Standby Current
I
CC
V
IL
V
IH
V
OL
V
OH
Notes:
V
CC
Active Current
Input Low Voltage
Input High Voltage
Output Low Voltage
Output High Voltage
1. V
CC
must be applied simultaneously or before V
PP
, and removed simultaneously 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
.
4
AT27C2048
0632F–EPROM–12/07
AT27C2048
9. AC Characteristics for Read Operation
AT27C2048
-55
Symbol
t
ACC(3)
t
CE(2)
t
OE(2)(3)
t
DF(4)(5)
t
OH(4)
Note:
Parameter
Address to Output Delay
CE to Output Delay
OE to Output Delay
Condition
CE = OE
= V
IL
OE = V
IL
CE = V
IL
Min
Max
55
55
20
20
7
0
Min
-90
Max
90
90
35
20
Units
ns
ns
ns
ns
ns
OE or CE High to Output Float, Whichever Occurred First
Output Hold from Address, CE or OE, Whichever
Occurred First
2, 3, 4, 5. See the AC Waveforms for Read Operation diagram.
10. 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.
5
0632F–EPROM–12/07
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