Preliminary W27E02
256K
×
8 ELECTRICALLY ERASABLE EPROM
1. GENERAL DESCRIPTION
The W27E02 is a high speed, low power consumption Electrically Erasable and Programmable Read
Only Memory organized as 262,144
×
8 bits. It requires only one supply in the range of 5.0V
±
10% in
normal read mode. The W27E02 provides an electrical chip erase function.
2. FEATURES
•
•
•
•
•
•
Single power supply voltage: 5.0V
±10%
High speed access time: 70/90 nS (max.)
Read operating current: 30 mA (max.)
Erase/Programming operating current:
30 mA (max.)
Standby current: 20
µA
(max.)
+12V erase/programming voltage
•
Fully static operation
•
All inputs and outputs directly TTL/CMOS
compatible
•
Three-state outputs
•
Available packages: 32-pin 600 mil DIP, 32-lead
PLCC and 32-lead STSOP
3. PIN CONFIGURATIONS
4. BLOCK DIAGRAM
V
DD
Vss
V
PP
Vpp
A16
A15
A12
A7
A6
A5
A4
A3
A2
A1
A0
Q0
Q1
Q2
Vss
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
32-pin
PDIP
32
31
30
29
28
27
26
25
24
23
22
21
20
19
18
17
V
DD
#PGM
A17
A14
A13
A8
A9
A11
#OE
A10
#CE
Q7
Q6
Q5
Q4
Q3
A7
A6
A5
A4
A3
A2
A1
A0
Q0
4
5
6
7
8
9
10
11
12 1
13 4
3 2
1
A A A
1 1 1
2 5 6
V
p
p
#
V P A
D G 1
D M
7
3
2
3
1
3
0 29
28
27
26
25
24
23
2 22
0 21
#PGM
#CE
#OE
CONTROL
OUTPUT
BUFFER
Q0
.
.
Q7
32-lead PLCC
1
5
1
6
1 1
7 8
1
9
A14
A13
A8
A9
A11
#OE
A10
#CE
Q7
A0
.
.
A17
DECODER
CORE
ARRAY
Q Q V Q Q Q Q
1 2 s 3 4 5 6
s
5. PIN DESCRIPTION
A11
A9
A8
A13
A14
A17
#PGM
V
DD
V
PP
A16
A15
A12
A7
A6
A5
A4
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
32
31
30
29
28
27
32-lead STSOP
26
25
24
23
22
21
20
19
18
17
#OE
A10
#CE
Q7
Q6
Q5
Q4
Q3
V SS
Q2
Q1
Q0
A0
A1
A2
A3
SYMBOL
A0
−
A17
Q0
−
Q7
#CE
#OE
#PGM
V
PP
V
DD
Vss
NC
DESCRIPTION
Address Inputs
Data Inputs/Outputs
Chip Enable
Output Enable
Program Enable
Program/Erase Supply Voltage
Power Supply
Ground
No Connection
-1-
Publication Release Date: May 30, 2002
Revision A1
Preliminary W27E02
6. FUNCTIONAL DESCRIPTION
Read Mode
Like conventional UVEPROMs, the W27E02 has two control functions and both of these produce data at
the outputs.
#CE is for power control and chip select. #OE controls the output buffer to gate data to the output pins.
When addresses are stable, the address access time (T
ACC
) is equal to the delay from #CE to output
(T
CE
), and data are available at the outputs T
OE
after the falling edge of #OE, if T
ACC
and T
CE
timings
are met.
Erase Mode
The erase operation is the only way to change data from "0" to "1." Unlike conventional UVEPROMs,
which use ultraviolet light to erase the contents of the entire chip (a procedure that requires up to half an
hour), the W27E02 uses electrical erasure. Generally, the chip can be erased within 100 mS by using an
EPROM writer with a special erase algorithm.
There are two ways to enter Erase mode. One is to raise V
PP
to V
PE
(12V), V
DD
= V
CE
(5.0V ), #CE low,
#OE high, A9 = V
HH
(12V), and all other address pins are kept at fixed low or high. Pulsing #PGM low
starts the erase operation. The other way is somewhat like flash, by programming two consecutive
commands into the device and then enter Erase mode. The two commands are loading Data = AA(hex)
to Addr. = 5555(hex) and Data = 10(hex) to Addr. = 2AAA(hex). Be careful to note that the #PGM pulse
widths of these two commands are different: One is 100
µS,
while the other is 100 mS. Please refer to
the Smart Erase Algorithm 1 & 2.
Erase Verify Mode
After an erase operation, all of the bytes in the chip must be verified to check whether they have been
successfully erased to "1" or not. The erase verify mode automatically ensures a substantial erase
margin. This mode will be entered after the erase operation if V
DD
= V
PE
(5.0V ), #CE low, and #OE low,
#PGM high
.
Program Mode
Programming is performed exactly as it is in conventional UVEPROMs, and programming is the only
way to change cell data from "1" to "0." The program mode is entered when V
PP
is raised to V
PP
(12V),
V
DD
= V
CP
(5.0V ), #CE low, #OE high, the address pins equal the desired addresses, and the input pins
equal the desired inputs. Pulsing #PGM low starts the programming operation.
Program Verify Mode
All of the bytes in the chip must be verified to check whether they have been successfully programmed
with the desired data or not. Hence, after each byte is programmed, a program verify operation should
be performed. The program verify mode automatically ensures a substantial program margin. This mode
will be entered after the program operation if V
PP
= V
PP
(12V), #CE low, #OE low
,
and #PGM high.
Erase/Program Inhibit
Erase or program inhibit mode allows parallel erasing or programming of multiple chips with different
data. When #CE high, erasing or programming of non-target chips is inhibited, so that except for the
#CE, the W27E02 may have common inputs.
-2-
Preliminary W27E02
Standby Mode
The standby mode significantly reduces V
DD
current. This mode is entered when #CE high. In standby
mode, all outputs are in a high impedance state, independent of #OE and #PGM.
Two-line Output Control
Since EPROMs are often used in large memory arrays, the W27E02 provides two control inputs for
multiple memory connections. Two-line control provides for lowest possible memory power dissipation
and ensures that data bus contention will not occur.
System Considerations
EPROM power switching characteristics require careful device decoupling. System designers are
concerned with three supply current issues: standby current levels (I
SB
), active current levels (I
CC
), and
transient current peaks produced by the falling and rising edges of #CE. Transient current magnitudes
depend on the device output's capacitive and inductive loading. Two-line control and proper decoupling
capacitor selection will suppress transient voltage peaks. Each device should have a 0.1
µF
ceramic
capacitor connected between its V
DD
and Vss. This high frequency, low inherent-inductance capacitor
should be placed as close as possible to the device. Additionally, for every eight devices, a 4.7
µF
electrolytic capacitor should be placed at the array's power supply connection between V
DD
and Vss.
The bulk capacitor will overcome voltage slumps caused by PC board trace inductances.
7. TABLE OF OPERATING MODES
V
DD
= 5.0V
±10
%, Vpp = Vp
E
= V
HH
= 12V, V
CP
= V
PE
= V
CE
= 5.0V, X = V
IH
or V
IL
PINS
MODE
#CE
#OE
#PGM
A0
A9
OTER
ADDR
V
DD
V
PP
OUTPUTS
Read
Output Disable
Standby (TTL)
Standby (CMOS)
Program
Program Verify
Program Inhibit
Erase1
Erase2
Erase Verify
Erase Inhibit
Product Identifier -
Manufacturer
Product Identifier -
Device
V
IL
V
IL
V
IH
V
DD
±0.3V
V
IL
V
IL
V
IH
V
IL
V
IL
V
IL
V
IH
V
IL
V
IL
V
IL
V
IH
X
X
V
IH
V
IL
X
V
IH
V
IH
V
IL
X
V
IL
V
IL
X
X
X
X
V
IL
V
IH
X
V
IL
V
IL
V
IH
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
V
DD
V
DD
V
DD
V
DD
V
CP
V
CP
V
CP
V
CE
V
CE
V
CE
V
PE
V
CE
V
DD
V
DD
V
DD
V
DD
V
DD
V
DD
V
PP
V
PP
V
PP
V
PE
V
CP
V
CP
V
PP
V
PE
V
DD
V
DD
D
OUT
High Z
High Z
High Z
D
IN
D
OUT
High Z
FF (Hex)
AA (Hex)
10 (Hex)
D
OUT
High Z
DA (Hex)
85 (Hex)
X
X
X
X
X
X
X
X
X
V
IL
V
PE
First command:
Addr. = 5555 (hex)
Second command:
Addr. = 2AAA (hex)
X
X
X
X
X
X
V
IL
V
IH
V
HH
V
HH
X
X
-3-
Publication Release Date: May 30, 2002
Revision A1
Preliminary W27E02
8. DC CHARACTERISTICS
Absolute Maximum Ratings
PARAMETER
Operation Temperature
Storage Temperature
Voltage on all Pins with Respect to Ground Except V
DD,
V
PP
and A9 Pins
Voltage on V
DD
Pin with Respect to Ground
Voltage on V
PP
Pin with Respect to Ground
Voltage on A9 Pin with Respect to Ground
RATING
0 to +70
-65 to +125
-0.5 to V
DD
+0.5
-0.5 to +7.0
-0.5 to +14.5
-0.5 to +14.5
UNIT
°C
°C
V
V
V
V
Note: Exposure to conditions beyond those listed under Absolute Maximum Ratings may adversely affect the life and reliability
of the device.
9. CAPACITANCE
(V
DD
= 5.0V
±10%,
T
A
= 25° C, f = 1 MHz)
PARAMETER
Input Capacitance
Output Capacitance
SYMBOL
C
IN
C
OUT
CONDITIONS
V
IN
= 0V
V
OUT
= 0V
MAX.
6
12
UNIT
pF
pF
10. READ OPERATION DC CHARACTERISTICS
(V
DD
= 5.0V
±10%,
T
A
= 0 to 70° C)
PARAMETER
Input Load Current
Output Leakage
Current
Standby V
DD
Current
(TTL input)
Standby V
DD
Current
(CMOS input)
V
DD
Operating Current
V
PP
Operating Current
Input Low Voltage
Input High Voltage
Output Low Voltage
Output High Voltage
V
PP
Operating Voltage
SYM.
I
LI
I
LO
I
SB
I
SB
1
I
CC
I
PP
V
IL
V
IH
V
OL
V
OH
V
PP
CONDITIONS
V
IN
= 0V to V
DD
V
OUT
= 0V to V
DD
#CE = V
IH
#CE = V
DD
±0.2V
#CE = V
IL,
I
OUT
= 0 mA,
f = 5 MHz
V
PP
= V
DD
-
-
I
OL
= 1.6 mA
I
OH
= -0.1 mA
-
LIMITS
MIN.
-5
-10
-
-
-
-
-0.3
2.0
-
2.4
V
DD -
0.7
TYP.
-
-
-
-
-
-
-
-
-
-
-
MAX.
5
10
1
100
30
10
0.8
V
DD
+0.5
0.4
-
V
DD
UNIT
µA
µA
mA
µA
mA
µA
V
V
V
V
V
-4-
Preliminary W27E02
Program/Erase DC Characteristics
(T
A
= 25° C, V
DD
= 5.0V
±10
%, V
HH
= 12V)
PARAMETER
Input Load Current
V
DD
Program Current
V
DD
Erase Current
V
PP
Program Current
V
PP
Erase Current
Input Low Voltage
Input High Voltage
Output Low Voltage (Verify)
Output High Voltage (Verify)
A9 Silicon I.D. Voltage
A9 Erase Voltage
V
PP
Program Voltage
V
PP
Erase Voltage
V
DD
Supply Voltage
(Program)
V
DD
Supply Voltage (Erase)
V
DD
Supply Voltage (Erase
Verify)
SYM.
I
LI
I
CP
I
CE
I
PP
I
PE
V
IL
V
IH
V
OL
V
OH
V
ID
V
ID
V
PP
V
PE
V
CP
V
CE
V
PE
CONDITIONS
MIN.
V
IN
= V
IL
or V
IH
#CE = V
IL,
#OE = V
IH,
#PGM = V
IL
#CE = V
IL,
#OE = V
IH,
#PGM = V
IL
, A9 = V
HH
#CE = V
IL,
#OE = V
IH,
#PGM = V
IL
#CE = V
IL,
#OE = V
IH,
#PGM = V
IL
, A9 = V
HH
-
-
I
OL
= 2.1 mA
I
OH
= -0.4 mA
-
-
-
-
-
-
-
-10
-
-
-
-
-0.3
2.4
-
2.4
11.5
11.75
11.75
11.75
4.5
4.5
-
LIMITS
TYP.
-
-
-
-
-
-
-
-
-
12.0
12.0
12.0
12.0
5.0
5.0
5.0
MAX.
10
30
30
30
30
0.8
5.5
0.45
-
12.5
14.25
12.25
14.25
5.5
5.5
-
UNIT
µA
mA
mA
mA
mA
V
V
V
V
V
V
V
V
V
V
V
Note: V
DD
must be applied simultaneously or before V
PP
and removed simultaneously or after V
PP
.
-5-
Publication Release Date: May 30, 2002
Revision A1