AT27C2048
1
Features
Fast Read Access Time - 55 ns
Low Power CMOS Operation
100
A Maximum Standby
35 mA Maximum Active at 5 MHz
JEDEC Standard Packages
40-Lead 600 mil PDIP
44-Lead PLCC
40-Lead TSOP (10 mm X 14 mm)
Direct Upgrade from 512K bit and 1M bit
(AT27C516 and AT27C1024) EPROMs
5V
10% Power Supply
High Reliability CMOS Technology
2,000V ESD Protection
200 mA Latchup Immunity
Rapid
TM
Programming Algorithm - 50
s/word (typical)
CMOS and TTL Compatible Inputs and Outputs
Integrated Product Identification Code
Commercial and Industrial Temperature Ranges
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 sin-
gle 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.
TSOP Top View
Type 1
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
A9
A10
A11
A12
A13
A14
A15
A16
PGM
VCC
VPP
CE
O15
O14
O13
O12
O11
O10
O9
O8
GND
A8
A7
A6
A5
A4
A3
A2
A1
A0
OE
O0
O1
O2
O3
O4
O5
O6
O7
GND
PDIP Top View
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
VPP
CE
O15
O14
O13
O12
O11
O10
O9
O8
GND
O7
O6
O5
O4
O3
O2
O1
O0
OE
VCC
PGM
A16
A15
A14
A13
A12
A11
A10
A9
GND
A8
A7
A6
A5
A4
A3
A2
A1
A0
PLCC Top View
7
8
9
10
11
12
13
14
15
16
17
39
38
37
36
35
34
33
32
31
30
29
O12
O11
O10
O9
O8
GND
NC
O7
O6
O5
O4
A13
A12
A11
A10
A9
GND
NC
A8
A7
A6
A5
6
5
4
3
2
1
44
43
42
41
40
18
19
20
21
22
23
24
25
26
27
28
O3
O2
O1
O0
OE
DC
A0
A1
A2
A3
A4
O13
O14
O15
CE
VPP
DC
VCC
PGM
A16
A15
A14
2-Megabit
(128K x 16)
OTP EPROM
AT27C2048
0632B-A06/97
Pin Configurations
Note:
Both GND pins must be con-
nected.
Pin Name
Function
A0 - A16
Addresses
O0 - O15
Outputs
CE
Chip Enable
OE
Output Enable
PGM
Program
NC
No Connect
Note:
PLCC package pins 1 and 23
are DON'T CONNECT.
(continued)
AT27C2048
2
Description
In read mode, the AT27C2048 typically consumes 15 mA.
Standby mode supply current is typically less than 10
A
.
T h e A T 2 7 C 2 0 4 8 i s a va i l a b l e i n i n d u s t r y s t a n d a rd
JEDEC-approved one-time programmable (OTP) plastic
PDIP, PLCC, and TSOP 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 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 50
s/word. The Integrated Prod-
uct Identification Code electronically identifies the device
and manufacturer. This feature is used by industry stan-
dard programming equipment to select the proper program-
ming algorithms and voltages.
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
F 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
F 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.
AT27C2048
3
Block Diagram
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)
Operating Modes
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
.
Mode/Pin
CE
OE
PGM
Ai
V
PP
Outputs
Read
V
IL
V
IL
X
(1)
Ai
X
(1)
D
OUT
Output Disable
X
V
IH
X
X
X
High Z
Standby
V
IH
X
X
X
X
(5)
High Z
Rapid Program
(2)
V
IL
V
IH
V
IL
Ai
V
PP
D
IN
PGM Verify
V
IL
V
IL
V
IH
Ai
V
PP
D
OUT
PGM Inhibit
V
IH
X
X
X
V
PP
High Z
Product Identification
(4)
V
IL
V
IL
X
A9 = V
H
(3)
A0 = V
IH
or V
IL
A1 - A16 = V
IL
V
CC
Identification Code
*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.
Note:
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.
AT27C2048
4
DC and AC Operating Conditions for Read Operation
DC and Operating Characteristics for Read Operation
Notes:
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
.
AC Characteristics for Read Operation
Notes:
1.
2, 3, 4, 5. See the AC Waveforms for Read Operation diagram.
AT27C2048
-55
-70
-90
-12
-15
Operating
Temperature
(Case)
Com.
0
C - 70
C
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
-40
C - 85
C
V
CC
Power Supply
5V
10%
5V
10%
5V
10%
5V
10%
5V
10%
Symbol
Parameter
Condition
Min
Max
Units
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
35
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
AT27C2048
-55
-70
-90
-12
-15
Symbol
Parameter
Condition
Min
Max
Min
Max
Min
Max
Min
Max
Min
Max
Units
t
ACC
(3)
Address to
Output Delay
CE = OE
= V
IL
55
70
90
120
150
ns
t
CE
(2)
CE to Output Delay
OE = V
IL
55
70
90
120
150
ns
t
OE
(2)(3)
OE to Output Delay
CE = V
IL
20
30
35
40
50
ns
t
DF
(4)(5)
OE or CE High to
Output Float,
whichever occurred
first
20
20
20
30
35
ns
t
OH
(4)
Output Hold from
Address, CE or OE,
whichever occurred
first
7
7
0
0
0
ns
AT27C2048
5
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.
Input Test Waveforms and Measurement Levels
For -55 devices only:
t
R
, t
F
< 5 ns (10% to 90%)
For -70, -90, -12 and -15
devices:
t
R
, t
F
< 20 ns (10% to 90%)
Pin Capacitance
(f = 1 MHz T = 25C)
(1)
Note:
Typical values for nominal supply voltage. This parameter is only sampled and is not 100% tested.
Typ
Max
Units
Conditions
C
IN
4
10
pF
V
IN
= 0V
C
OUT
8
12
pF
V
OUT
= 0V
Output Test Load
Note:
CL = 100 pF including jig
capacitance, except for the -55
devices, where CL = 30 pF.
PDF 
ZIP