CY7C4255-15AC Cypress Semiconductor Corp, CY7C4255-15AC Datasheet - Page 2
![](/photos/31/34/313434/42864tqfp_sml.jpg)
CY7C4255-15AC
Manufacturer Part Number
CY7C4255-15AC
Description
Manufacturer
Cypress Semiconductor Corp
Datasheet
1.CY7C4255-15AC.pdf
(23 pages)
Specifications of CY7C4255-15AC
Configuration
Dual
Density
144Kb
Access Time (max)
10ns
Word Size
18b
Organization
8Kx18
Sync/async
Synchronous
Expandable
Yes
Bus Direction
Uni-Directional
Package Type
TQFP
Clock Freq (max)
66.7MHz
Operating Supply Voltage (typ)
5V
Operating Supply Voltage (min)
4.5V
Operating Supply Voltage (max)
5.5V
Supply Current
45mA
Operating Temp Range
0C to 70C
Operating Temperature Classification
Commercial
Mounting
Surface Mount
Pin Count
64
Lead Free Status / Rohs Status
Not Compliant
Available stocks
Company
Part Number
Manufacturer
Quantity
Price
Company:
Part Number:
CY7C4255-15AC
Manufacturer:
CYPRESS
Quantity:
591
Pin Configurations
Pin Description
The CY7C4255/65/65A provides five status pins. These pins are
decoded to determine one of five states: Empty, Almost Empty,
Half Full, Almost Full, and Full. The Half Full flag shares the WXO
pin. This flag is valid in the standalone and width-expansion
configurations. In the depth expansion, this pin provides the
expansion out (WXO) information that is used to signal the next
FIFO when it is activated.
The Empty and Full flags are synchronous, that is, they change
state relative to either the Read Clock (RCLK) or the Write Clock
Table 1. Selection Guide
Table 2. Density and Package
Document #: 38-06004 Rev. *E
Maximum Frequency (MHz)
Maximum Access Time (ns)
Minimum Cycle Time (ns)
Minimum Data or Enable Set-Up (ns)
Minimum Data or Enable Hold (ns)
Maximum Flag Delay (ns)
Active Power Supply
Current (I
Description
CC1
Package
Density
) (mA)
Description
Commercial
Industrial
Figure 1. 64-Pin TQFP/STQFP (Top View)
D
D
D
D
D
D
D
D
D
D
D
D
D
D
D
D
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
7C4255/65-10
64-pin TQFP, STQFP
CY7C4255
100
0.5
10
45
50
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
8
3
8
8K x 18
CY7C4265/65A
CY7C4255
7C4255/65/65A-15
(WCLK). When entering or exiting the Empty states, the flag is
updated exclusively by the RCLK. The flag denoting Full states
is updated exclusively by WCLK. The synchronous flag archi-
tecture guarantees that the flags remain valid from one clock
cycle to the next. The Almost Empty/Almost Full flags become
synchronous if the V
tions are fabricated using an advanced 0.5μ CMOS
technology. Input ESD protection is greater than 2001V, and
latch up is prevented by the use of guard rings.
66.7
CY7C4255, CY7C4265, CY7C4265A
10
15
10
45
50
4
1
48
47
46
45
44
43
42
41
40
39
38
37
36
35
34
33
CC
7C4255/65-25
/SMODE is tied to V
64-pin TQFP, STQFP
40
15
25
15
45
50
Q
Q
GND
Q
Q
V
Q
Q
GND
Q
Q
Q
Q
GND
Q
V
6
1
CC
CC
14
13
12
11
10
9
8
7
6
5
4
CY7C4265/65A
16K x18
7C4255/65-35
SS
. All configura-
28.6
20
35
20
45
50
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