2K x 8 Reprogrammable Registered PROM
CY7C245A
Cypress Semiconductor Corporation
•
198 Champion Court
•
San Jose
, CA 95134-1709
•
408-943-2600
Document #: 38-04007 Rev. *E
Revised August 17, 2006
Features
• Windowed for reprogrammability
• CMOS for optimum speed/power
• High speed
— 15-ns address set-up
— 10-ns clock to output
• Low power
— 330 mW (commercial) for -25 ns
— 660 mW (military)
• Programmable synchronous or asynchronous output
enable
• On-chip edge-triggered registers
• Programmable asynchronous register (INIT)
• EPROM technology, 100% programmable
• Slim, 300-mil, 24-pin plastic or hermetic DIP
•5V
±10% V
CC, commercial and military
• TTL-compatible I/O
• Direct replacement for bipolar PROMs
• Capable of withstanding greater than 2001V static
discharge
Functional Description
The CY7C245A is a high-performance, 2K x 8, electrically
programmable, read-only memory packaged in a slim 300-mil
plastic or hermetic DIP. The ceramic package may be
equipped with an erasure window; when exposed to UV light
the PROM is erased and can then be reprogrammed. The
memory cells utilize proven EPROM floating-gate technology
and byte-wide intelligent programming algorithms.
The CY7C245A replaces bipolar devices and offers the advan-
tages of lower power, reprogrammability, superior perfor-
mance and high programming yield. The EPROM cell requires
only 12.5V for the supervoltage, and low current requirements
allow gang programming. The EPROM cells allow each
memory location to be tested 100%, because each location is
written into, erased, and repeatedly exercised prior to encap-
sulation. Each PROM is also tested for AC performance to
guarantee that after customer programming the product will
meet AC specification limits.
The CY7C245A has an asynchronous initialize function (INIT).
This function acts as a 2049th 8-bit word loaded into the
on-chip register. It is user programmable with any desired
word, or may be used as a PRESET or CLEAR function on the
outputs. INIT is triggered by a low level, not an edge.
Logic Block Diagram
Pin Configurations
1
2
3
4
5
6
7
8
9
10
11
12
16
17
18
19
20
24
23
22
21
13
14
A7
A6
A5
A4
A3
A2
A1
A0
O0
O1
O2
GND
VCC
A8
A9
INIT
CP
O7
O6
O4
O5
O3
PROGRAMMABLE
ARRAY
MULTIPLEXER
15
8-BIT
EDGE-
REGISTER
TRIGGERED
O
7
O
6
O
5
O
4
O
3
O
2
O
1
O
0
CP
CP
E/E S
E/ES
28
4
5
6
7
8
9
10
32 1
27
1314151617
26
25
24
23
22
21
20
11
12
19
O0
18
NC
A0
A4
A3
A10
NC
INIT
E/ES
O7
O6
A2
A1
CP
INIT
PROGRAMMABLE
MULTIPLEXER
DQ
C
A10
ADDRESS
DECODER
A0
A1
A2
A3
A4
A5
A6
A8
A9
A10
A7
COLUMN
ADDRESS
ROW
ADDRESS
DIP Top View
LCC/PLCC (Opaque only) Top View
Selection Guide
7C245A-15
7C245A-18
7C245A-25
7C245A-35
Unit
Minimum Address Set-up Time
15
18
25
35
ns
Maximum Clock to Output
10
12
12
15
ns
Maximum Operating Current Standard
Commercial
120
120
90
90
mA
Military
120
120
120
mA
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