1CY 7C24 4
CY7C243
CY7C244
4Kx8 Reprogrammable PROM
Features
•
CMOS for optimum speed/power
•
Windowed for reprogrammability
•
High speed
Functional Description
The CY7C243 and CY7C244 are high-performance 4K x 8
CMOS PROMs. The CY7C243 and CY7C244 are packaged in
300-mil-wide and 600-mil-wide packages respectively. The re-
programmable packages are equipped with an erasure win-
dow. When exposed to UV light, these PROMs are erased and
can then be reprogrammed. The memory cells utilize proven
EPROM floating-gate technology and byte-wide intelligent pro-
gramming algorithms.
The CY7C243 and CY7C244 are plug-in replacements for bi-
polar devices and offer the advantages of lower power, supe-
rior performance and programming yield. The EPROM cell re-
quires only 12.5V for the supervoltage and low current
requirements allow for gang programming. The EPROM cells
allow for each memory location to be tested 100%, as each
cell is programmed, erased, and repeatedly exercised prior to
encapsulation. Each PROM is also tested for AC performance
to guarantee that after customer programming the product will
meet DC and AC specification limits.
Read is accomplished by placing an active LOW signal on CS
1
and an active HIGH on CS
2
. The contents of the memory lo-
cation addressed by the address line (A
0
−
A
11
) will become
available on the output lines (O
0
−
O
7
).
—
20 ns (commercial)
—
25 ns (military)
•
Low power
—
550 mW (commercial)
—
660 mW (military)
•
EPROM technology 100% programmable
•
300-mil or 600-mil packaging available
•
5V
±
10% V
CC
, commercial and military
•
Capable of withstanding greater than 2001V static
discharge
•
TTL-compatible I/O
•
Direct replacement for bipolar PROMs
Logic Block Diagram
A
0
A
1
A
2
A
3
A
4
A
5
A
6
A
7
A
8
A
9
A
10
A
11
COLUMN
ADDRESS
O
3
ADDRESS
DECODER
O
4
O
5
ROW
ADDRESS
PROGRAM-
MABLE
ARRAY
COLUMN
MULTI-
PLEXER
O
7
Pin Configurations
DIP/Flatboat
Top View
A
7
A
6
A
5
A
4
A
3
A
2
A
1
A
0
O
0
O
1
O
2
GND
1
24
2
23
3
22
4
21
5
20
6
19
18
7
17
8
9 7C243 16
10
15
11 7C244 14
12
13
V
CC
A
8
A
9
A
10
CS
1
A
11
CS
2
O
7
O
6
O
5
O
4
O
3
C243-2
O
6
O
2
LCC/PLCC (Opaque Only)
Top View
4 3 2 1 2827 26
25
5
24
6
23
7
7C243
22
8
21
9
20
10
19
11
12 1314151617 18
O
1
A
4
A
3
A
2
A
1
A
0
NC
O
0
O
0
CS
1
CS
2
C243-1
A
10
CS
1
A
11
CS
2
NC
O
7
O
6
C243-3
Selection Guide
7C243-20
7C244-20
20
100
7C243-25
7C244-25
25
100
120
7C243-35
7C244-35
35
80
100
7C243-45
7C244-45
45
80
100
7C243-55
7C244-55
55
80
100
Maximum Access Time (ns)
Maximum Operating
Commercial
Current (mA)
Military
Cypress Semiconductor Corporation
•
3901 North First Street
•
San Jose
•
CA 95134 •
408-943-2600
May 1994 – Revised August 1994
CY7C243
CY7C244
Maximum Ratings
(Above which the useful life may be impaired. For user guide-
lines, not tested.)
Storage Temperature
...................................... −65°C
to+150°C
Ambient Temperature with
Power Applied...................................................
−55°C
to+125°C
Supply Voltage to Ground Potential
(V
CC
to GND)
........................................................−0.5V
to+7.0V
DC Voltage Applied to Outputs
in High Z State
......................................................−0.5V
to+7.0V
DC Input Voltage
.................................................−3.0V
to +7.0V
DC Program Voltage
(Pin 19 DIP, Pin 23 LCC) ..............................................13.0V
Electrical Characteristics
Over the Operating Range
[3,4]
Static Discharge Voltage ........................................... >2001V
(per MIL-STD-883, Method 3015)
Latch-Up Current ..................................................... >200 mA
UV Exposure ................................................ 7258 Wsec/cm
2
Operating Range
Range
Commercial
Industrial
[1]
Military
[2]
Ambient
Temperature
0
°
C to + 70
°
C
−40
°
C to + 85
°
C
−55
°
C to + 125
°
C
V
CC
5V
±
10%
5V
±
10%
5V
±
10%
7C243-20, 25
7C244-20, 25
Parameter
V
OH
V
OH
V
OL
V
OL
V
IH
V
IL
I
IX
V
CD
I
OZ
I
OS
I
CC
Description
Output HIGH Voltage
Output HIGH Voltage
Output LOW Voltage
Output LOW Voltage
Input HIGH Level
Input LOW Level
Input Current
Input Diode Clamp Voltage
Output Leakage Current
Output Short Circuit Current
[5]
Power Supply Current
0 < V
OUT
< V
CC
,
Output Disabled
V
CC
= Max.,
V
OUT
= GND
V
CC
= Max.,
I
OUT
= 0 mA
Com’l
Mil
12
−10
−20
GND < V
IN
< V
CC
−10
Test Conditions
V
CC
= Min., I
OH
=
−2.0
mA
V
CC
= Min., I
OH
=
−4.0
mA
V
CC
= Min., I
OL
= 8 mA
(6 mA Mil)
V
CC
= Min., I
OL
= 16 mA
2.0
V
CC
+ 0.3
0.8
+10
Note 4
+10
−90
100
120
13
50
0.4
Min.
2.4
Max.
7C243-35, 45, 55
7C244-35, 45, 55
Min.
Max.
Unit
V
2.4
V
V
0.4
2.0
V
CC
+ 0.3
0.8
−10
+10
Note 4
−10
−20
+10
−90
80
100
12
13
50
V
mA
µA
mA
mA
V
V
V
µA
V
PP
I
PP
Programming Supply Voltage
Programming Supply Current
Notes:
1. See the Ordering Information section regarding industrial temperature range specification.
2. T
A
is the “instant on” case temperature.
3. See the last page of this specification for Group A subgroup testing information.
4. See the “Introduction to CMOS PROMs” section of the Cypress Data Book for general information on testing.
5. For test purposes, not more than one output at a time should be shorted. Short circuit test duration should not exceed 30 seconds.
Capacitance
[4]
Parameter
C
IN
C
OUT
Description
Input Capacitance
Output Capacitance
Test Conditions
T
A
= 25°C, f = 1 MHz,
V
CC
= 5.0V
Max.
10
10
Unit
pF
pF
2
CY7C243
CY7C244
AC Test Loads and Waveforms
[4]
Test Load for -20 through-25 speeds
R1 500
(658Ω MIL)
5V
OUTPUT
30pF
INCLUDING
JIG AND
SCOPE
5V
OUTPUT
R2 333
Ω
(403Ω MIL)
5 pF
INCLUDING
JIG AND
SCOPE
R2 333Ω
(403Ω MIL)
R1 500Ω
(658Ω MIL)
3.0V
GND
≤
5 ns
ALL INPUT PULSES
90%
10%
90%
10%
≤
5 ns
C243-4
C243-5
(a) Normal Load
Equivalent to:
(b) High Z Load
TH ÈVENIN EQUIVALENT
R
TH
200Ω(250ΩMIL)
OUTPUT
2.0V(1.9VMIL)
Test Load for -35 through -55 speeds
R1 250Ω
5V
OUTPUT
30pF
INCLUDING
JIG AND
SCOPE
5V
OUTPUT
R2 167Ω
5 pF
INCLUDING
JIG AND
SCOPE
R2 167Ω
R1 250Ω
(c) Normal Load
Equivalent to:
THÈVENIN
EQUIVALENT
2.0V
(d) High Z Load
C243-6
OUTPUT
R
TH
100Ω
Switching Characteristics
Over the Operating Range
[2, 3, 4]
7C243-20
7C244-20
Parameter
t
AA
t
HZCS
(Com’l)
t
HZCS
(Mil)
t
ACS
(Com’l)
t
ACS
(Mil)
Description
Address to Output Valid
Chip Select Inactive to High Z
Chip Select Inactive to High Z
Chip Select Active to Output
Valid
Chip Select Active to Output
Valid
12
Min.
Max.
20
12
7C243-25
7C244-25
Min.
Max.
25
12
15
12
15
7C243-35
7C244-35
Min.
Max.
35
20
20
20
20
7C243-45
7C244-45
Min.
Max.
45
25
25
25
25
7C243-55
7C244-55
Min.
Max.
55
25
25
25
25
Unit
ns
ns
ns
ns
ns
3
CY7C243
CY7C244
Switching Waveforms
[4]
A
0
−
A
11
ADDRESS
CS
1
CS
2
t
AA
O
0
−
O
7
C243-7
t
HZCS
t
ACS
t
HZCS
t
ACS
Erasure Characteristics
Wavelengths of light less than 4000 Angstroms begin to erase
the devices in the windowed package. For this reason, an
opaque label should be placed over the window if the PROM
is exposed to sunlight or fluorescent lighting for extended pe-
riods of time.
The recommended dose of ultraviolet light for erasure is a
wavelength of 2537 Angstroms for a minimum dose (UV inten-
sity multiplied by exposure time) of 25 Wsec/cm
2
. For an ultra-
violet lamp with a 12 mW/cm
2
power rating, the exposure time
would be approximately 35 minutes. The CY7C243 or
CY7C244 needs to be within 1 inch of the lamp during erasure.
Table 1. Mode Selection.
Permanent damage may result if the PROM is exposed to
high-intensity UV light for an extended period of time. 7258
Wsec/cm
2
is the recommended maximum dosage.
Operating Modes
Read is the normal operating mode for a programmed device.
In this mode, all signals are normal TTL levels. The PROM is
addressed with a 12-bit field, an active LOW signal is applied
to CS
1
, an active HIGH is applied to CS
2
, and the contents of the
addressed location appear on the data out pins.
.
Pin Function
[6]
Read or Output Disable
Mode
Read
Output Disable
Output Disable
Notes:
6. X can be V
IL
or V
IH
.
A
11
V
PP
A
11
A
11
A
11
A
10
LATCH
A
10
A
10
A
10
A
9
PGM
A
9
A
9
A
9
A
8
VFY
A
8
A
8
A
8
CS
1
CS
1
V
IL
V
IH
X
CS
2
NA
V
IH
X
V
IL
O
7
- O
0
D
7
- D
0
O
7
- O
0
High Z
High Z
Program
Programming Information
Programming support is available from Cypress as well as
from a number of third-party software vendors. For detailed
programming information, including a listing of software pack-
ages, please see the PROM Programming Information located
at the end of this section. Programming algorithms can be ob-
tained from any Cypress representative.
s
4
CY7C243
CY7C244
Typical DC and AC Characteristic
NORMALIZED SUPPLY CURRENT
vs. SUPPLY VOLTAGE
1.6
1.4
1.1
1.2
1.0
1.0
0.8
0.6
4.0
T
A
=25°C
f = f
MAX
4.5
5.0
5.5
6.0
0.9
0.6
T
A
=25°C
0.8
−55
25
125
0.4
4.0
4.5
5.0
5.5
6.0
0.8
1.0
1.2
NORMALIZED SUPPLY CURRENT
vs. AMBIENT TEMPERATURE
1.2
NORMALIZED ACCESS TIME
vs. SUPPLY VOLTAGE
SUPPLYVOLTAGE(V)
AMBIENT TEMPERATURE (°C)
SUPPLY VOLTAGE (V)
NORMALIZED ACCESS TIME
vs. TEMPERATURE
1.6
1.4
40
1.2
30
1.0
0.8
0.6
−55
60
50
OUTPUT SOURCE CURRENT
vs. VOLTAGE
35
30
25
20
15
20
10
0
0
1.0
2.0
3.0
4.0
10
5
0
TYPICAL ACCESS TIME CHANGE
vs. OUTPUT LOADING
V
CC
=4.5V
T
A
=25°C
0
200
400
600
800 1000
25
125
AMBIENT TEMPERATURE (°C)
OUTPUT VOLTAGE (V)
CAPACITANCE (pF)
OUTPUT SINK CURRENT
vs. OUTPUT VOLTAGE
175
150
125
100
75
50
25
0
0.0
1.0
2.0
3.0
4.0
V
CC
=5.0V
T
A
=25°C
1.05
1.00
0.95
0.90
0.85
0.80
0.75
0.70
NORMALIZED SUPPLY CURRENT
vs. CYCLE PERIOD
V
CC
=5.5V
T
A
=25°C
0
25
50
75
100
OUTPUT VOLTAGE (V)
CYCLE PERIOD(ns)
]
5
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