CY7C4251V-25AXC [CYPRESS]
Low-Voltage 64/256/512/1K/2K/4K/8K x 9 Synchronous FIFOs; 低电压的64/256 / 512 / 1K / 2K / 4K / 8K ×9同步FIFO型号: | CY7C4251V-25AXC |
厂家: | CYPRESS |
描述: | Low-Voltage 64/256/512/1K/2K/4K/8K x 9 Synchronous FIFOs |
文件: | 总18页 (文件大小:522K) |
中文: | 中文翻译 | 下载: | 下载PDF数据表文档文件 |
CY7C4421V/4201V/4211V/4221VCY7C4231V/4241V/4251VLow-Voltage 64/256/512/1K/2K/4K/8K
x 9 Synchronous FIFOs
CY7C4421V/4201V/4211V/4221V
CY7C4231V/4241V/4251V
Low-Voltage 64/256/512/1K/2K/4K/8K x 9 Synchronous FIFOs
• Space saving 32-pin 7 mm × 7 mm TQFP
Featuresb
• 32-pin PLCC
• High-speed, low-power, first-in, first-out (FIFO)
memories
• Available in Pb-Free Packages
• 64 x 9 (CY7C4421V)
• 256 x 9 (CY7C4201V)
• 512 x 9 (CY7C4211V)
• 1K x 9 (CY7C4221V)
• 2K x 9 (CY7C4231V)
• 4K x 9 (CY7C4241V)
• 8K x 9 (CY7C4251V)
Functional Description
The CY7C42X1V are high-speed, low-power, FIFO memories
with clocked read and write interfaces. All are nine bits wide.
Programmable features include Almost Full/Almost Empty
flags. These FIFOs provide solutions for a wide variety of data
buffering needs, including high-speed data acquisition, multi-
processor interfaces, and communications buffering.
These FIFOs have 9-bit input and output ports that are
controlled by separate clock and enable signals. The input port
is controlled by a Free-Running Clock (WCLK) and two Write
Enable pins (WEN1, WEN2/LD).
• High-speed 66-MHz operation (15-ns read/write cycle
time)
• Low power (ICC = 20 mA)
When WEN1 is LOW and WEN2/LD is HIGH, data is written
into the FIFO on the rising edge of the WCLK signal. While
WEN1, WEN2/LD is held active, data is continually written into
the FIFO on each WCLK cycle. The output port is controlled in
a similar manner by a Free-Running Read Clock (RCLK) and
two Read Enable Pins (REN1, REN2). In addition, the
CY7C42X1V has an Output Enable Pin (OE). The Read
(RCLK) and Write (WCLK) clocks may be tied together for
single-clock operation or the two clocks may be run indepen-
dently for asynchronous read/write applications. Clock
frequencies up to 66 MHz are achievable.
• 3.3V operation for low power consumption and easy
integration into low-voltage systems
• 5V-tolerant inputs VIH max = 5V
• Fully asynchronous and simultaneous read and write
operation
• Empty, Full, and Programmable Almost Empty and
Almost Full status flags
• TTL compatible
• Output Enable (OE) pin
Depth expansion is possible using one enable input for system
control, while the other enable is controlled by expansion logic
to direct the flow of data.
• Independent read and write enable pins
• Center power and ground pins for reduced noise
• Width expansion capability
Pin Configuration
Logic Block Diagram
D
0− 8
PLCC
Top View
INPUT
REGISTER
4
3
2
1 323130
29
28
D
D
PAF
PAE
GND
REN1
RCLK
REN2
OE
RS
WEN1
1
5
6
7
8
9
0
27 WCLK
26
25
24
23
22
21
WCLKWEN1 WEN2/LD
WEN2/LD
V
CC
FLAG
PROGRAM
REGISTER
Q
Q
Q
Q
10
11
12
13
8
7
6
5
WRITE
CONTROL
14151617181920
EF
PAE
PAF
FF
FLAG
LOGIC
Dual Port
RAM Array
64 x 9
WRITE
POINTER
READ
POINTER
8Kx 9
RESET
LOGIC
RS
THREE-STATE
OUTPUTREGISTER
READ
CONTROL
OE
Q
0− 8
RCLK REN1 REN2
Cypress Semiconductor Corporation
Document #: 38-06010 Rev. *B
•
3901 North First Street
•
San Jose, CA 95134
•
408-943-2600
Revised July 14, 2005
CY7C4421V/4201V/4211V/4221V
CY7C4231V/4241V/4251V
Selection Guide
CY7C42X1V-15
CY7C42X1V-25
CY7C42X1V-35
Unit
MHz
ns
Maximum Frequency
66.7
11
15
4
40
15
25
6
28.6
20
35
7
Maximum Access Time
Minimum Cycle Time
ns
Minimum Data or Enable Set-up
Minimum Data or Enable Hold
Maximum Flag Delay
ns
1
1
2
ns
10
20
15
20
20
20
ns
Active Power Supply Current
Commercial
mA
CY7C4421V
CY7C4201V
256 x 9
CY7C4211V
512 x 9
CY7C4221V
CY7C4231V
CY7C4241V
CY7C4251V
Density
64 x 9
1K x 9
2K x 9
4K x 9
8K x 9
Pin Definitions
Signal Name
Description
I/O
Description
D0−8
Data Inputs
I
O
I
Data Inputs for 9-bit bus.
Data Outputs for 9-bit bus.
Q0−8
Data Outputs
Write Enable 1
WEN1
The only write enable when device is configured to have programmable flags.
Data is written on a LOW-to-HIGH transition of WCLK when WEN1 is asserted and FF is
HIGH. If the FIFO is configured to have two write enables, data is written on a LOW-to-HIGH
transition of WCLK when WEN1 is LOW and WEN2/LD and FF are HIGH.
WEN2/LD
Dual Mode Pin
Write Enable 2
Load
I
I
If HIGH at reset, this pin operates as a second write enable. If LOW at reset, this
pin operates as a control to write or read the programmable flag offsets. WEN1 must be
LOW and WEN2 must be HIGH to write data into the FIFO. Data will not be written into the FIFO
if the FF is LOW. If the FIFO is configured to have programmable flags, WEN2/LD is held LOW
to write or read the programmable flag offsets.
REN1, REN2 Read Enable
Inputs
I
I
Enables the device for Read operation.
WCLK
Write Clock
The rising edge clocks data into the FIFO when WEN1is LOW and WEN2/LD is HIGH
and the FIFO is not Full. When LD is asserted, WCLK writes data into the programmable
flag-offset register.
RCLK
Read Clock
I
The rising edge clocks data out of the FIFO when REN1and REN2 are LOW and the
FIFO is not Empty. When WEN2/LD is LOW, RCLK reads data out of the programmable flag
offset register.
EF
Empty Flag
Full Flag
O
O
O
When EF is LOW, the FIFO is empty. EF is synchronized to RCLK.
When FF is LOW, the FIFO is full. FF is synchronized to WCLK.
FF
PAE
Programmable
Almost Empty
When PAE is LOW, the FIFO is almost empty based on the almost empty offset value
programmed into the FIFO.
PAF
RS
Programmable
Almost Full
O
I
When PAF is LOW, the FIFO is almost full based on the almost full offset value
programmed into the FIFO.
Reset
Resets device to empty condition. A reset is required before an initial read or write
operation after power-up.
OE
Output Enable
I
When OE is LOW, the FIFO’s data outputs drive the bus to which they are connected. If
OE is HIGH, the FIFO’s outputs are in High Z (high-impedance) state.
When entering or exiting the Empty and Almost Empty states,
the flags are updated exclusively by the RCLK. The flags
denoting Almost Full and Full states are updated exclusively
by WCLK. The synchronous flag architecture guarantees that
the flags maintain their status for at least one cycle
Functional Description (continued)
The CY7C42X1V provides four status pins: Empty, Full, Almost
Empty, Almost Full. The Almost Empty/Almost Full flags are
programmable to single word granularity. The programmable flags
default to Empty-7 and Full-7.
All configurations are fabricated using an advanced 0.65µ
P-Well CMOS technology. Input ESD protection is greater than
2001V, and latch-up is prevented by the use of guard rings.
The flags are synchronous, i.e., they change state relative to
either the Read Clock (RCLK) or the Write Clock (WCLK).
Document #: 38-06010 Rev. *B
Page 2 of 18
CY7C4421V/4201V/4211V/4221V
CY7C4231V/4241V/4251V
Write Enable 2/Load (WEN2/LD). This is a dual-purpose pin.
The FIFO is configured at Reset to have programmable flags
or to have two write enables, which allows for depth
expansion. If Write Enable 2/Load (WEN2/LD) is set active
HIGH at Reset (RS=LOW), this pin operates as a second write
enable pin.
Architecture
The CY7C42X1V consists of an array of 64 to 8K words of nine
bits each (implemented by a dual-port array of SRAM cells),
a read pointer, a write pointer, control signals (RCLK, WCLK,
REN1, REN2, WEN1, WEN2, RS), and flags (EF, PAE, PAF,
FF.)
If the FIFO is configured to have two write enables, when Write
Enable (WEN1) is LOW and Write Enable 2/Load (WEN2/LD)
is HIGH, data can be loaded into the input register and RAM
array on the LOW-to-HIGH transition of every write clock
(WCLK.) Data is stored in the RAM array sequentially and
independently of any on-going read operation.
Resetting the FIFO
Upon power-up, the FIFO must be reset with a Reset (RS)
cycle. This causes the FIFO to enter the Empty condition
signified by EF being LOW. All data outputs (Q0-8) go LOW
tRSF after the rising edge of RS. In order for the FIFO to reset
to its default state, a falling edge must occur on RS and the
user must not read or write while RS is LOW. All flags are
guaranteed to be valid tRSF after RS is taken LOW.
Programming
When WEN2/LD is held LOW during Reset, this pin is the load
(LD) enable for flag offset programming. In this configuration,
WEN2/LD can be used to access the four 8-bit offset registers
contained in the CY7C42X1V for writing or reading data to
these registers.
FIFO Operation
When the WEN1 signal is active LOW and WEN2 is active HIGH,
data present on the D0-8 pins is written into the FIFO on each
rising edge of the WCLK signal. Similarly, when the REN1 and
REN2 signals are active LOW, data in the FIFO memory will
be presented on the Q0-8 outputs. New data will be presented
on each rising edge of RCLK while REN1 and REN2 are
active. REN1 and REN2 must set up tENS before RCLK for it
to be a valid read function. WEN1 and WEN2 must occur tENS
before WCLK for it to be a valid write function.
When the device is configured for programmable flags and
both WEN2/LD and WEN1 are LOW, the first LOW-to-HIGH
transition of WCLK writes data from the data inputs to the
empty offset Least Significant Bit (LSB) register. The second,
third, and fourth LOW-to-HIGH transitions of WCLK store data
in the empty offset Most Significant Bit (MSB) register, full
offset LSB register, and full offset MSB register, respectively,
when WEN2/LD and WEN1 are LOW. The fifth LOW-to-HIGH
transition of WCLK while WEN2/LD and WEN1 are LOW
writes data to the empty LSB register again. Figure 1 shows
the register sizes and default values for the various device
types.
An Output Enable (OE) pin is provided to three-state the Q0-8
outputs when OE is asserted. When OE is enabled (LOW), data
in the output register will be available to the Q0-8 outputs after tOE
.
The FIFO contains overflow circuitry to disallow additional
writes when the FIFO is full, and underflow circuitry to disallow
additional reads when the FIFO is empty. An empty FIFO
maintains the data of the last valid read on its Q0-8 outputs
even after additional reads occur.
It is not necessary to write to all the offset registers at one time.
A subset of the offset registers can be written; then by bringing
the WEN2/LD input HIGH, the FIFO is returned to normal read
and write operation. The next time WEN2/LD is brought LOW,
a write operation stores data in the next offset register in
sequence.
Write Enable 1 (WEN1). If the FIFO is configured for program-
mable flags, Write Enable 1 (WEN1) is the only write enable
control pin. In this configuration, when Write Enable 1 (WEN1)
is LOW, data can be loaded into the input register and RAM
array on the LOW-to-HIGH transition of every write clock
(WCLK). Data is stored is the RAM array sequentially and
independently of any on-going read operation.
The contents of the offset registers can be read to the data
outputs when WEN2/LD is LOW and both REN1 and REN2
are LOW. LOW-to-HIGH transitions of RCLK read register
contents to the data outputs. Writes and reads should not be
performed simultaneously on the offset registers.
Document #: 38-06010 Rev. *B
Page 3 of 18
CY7C4421V/4201V/4211V/4221V
CY7C4231V/4241V/4251V
64 x 9
6
256 x 9
7
512 x 9
1K x 9
7
0
0
0
0
0
0
0
0
0
0
8
8
8
8
8
8
8
8
8
8
8
8
7
8
8
8
8
Empty Offset (LSB) Reg.
Default Value = 007h
Empty Offset (LSB) Reg.
Default Value = 007h
Empty Offset (LSB) Reg.
Default Value = 007h
Empty Offset (LSB) Reg.
Default Value = 007h
0
0
0
0
1
(MSB)
(MSB)
00
0
0
6
7
7
7
Full Offset (LSB) Reg
Default Value = 007h
Full Offset (LSB) Reg
Default Value = 007h
Full Offset (LSB) Reg
Default Value = 007h
Full Offset (LSB) Reg
Default Value = 007h
0
1
(MSB)
0
(MSB)
00
2K x 9
4K x 9
8K x 9
0
0
0
0
0
0
0
0
0
8
8
8
8
7
8
8
8
8
7
8
8
8
8
7
Empty Offset (LSB) Reg.
Default Value = 007h
Empty Offset (LSB) Reg.
Default Value= 007h
Empty Offset (LSB) Reg.
Default Value = 007h
0
0
0
2
3
4
(MSB)
0000
(MSB)
00000
(MSB)
000
7
7
7
Full Offset (LSB) Reg
Default Value = 007h
Full Offset (LSB) Reg
Default Value= 007h
Full Offset (LSB) Reg
Default Value = 007h
2
3
4
(MSB)
000
(MSB)
0000
(MSB)
00000
Figure 1. Offset Register Location and Default Values
Programmable Flag (PAE, PAF) Operation
The number formed by the empty offset least significant bit
register and empty offset most significant register is referred
to as n and determines the operation of PAE. PAE is synchro-
nized to the LOW-to-HIGH transition of RCLK by one flip-flop
and is LOW when the FIFO contains n or fewer unread words.
PAE is set HIGH by the LOW-to-HIGH transition of RCLK
when the FIFO contains (n+1) or greater unread words.
Whether the flag offset registers are programmed as
described in Table 1 or the default values are used, the
programmable Almost Empty Flag (PAE) and programmable
Almost Full Flag (PAF) states are determined by their corre-
sponding offset registers and the difference between the read
and write pointers.
The number formed by the full offset least significant bit
register and full offset most significant bit register is referred to
as m and determines the operation of PAF. PAE is synchro-
nized to the LOW-to-HIGH transition of WCLK by one flip-flop
and is set LOW when the number of unread words in the FIFO
is greater than or equal to CY7C4421V (64 – m), CY7C4201V
(256 – m), CY7C4211V (512 – m), CY7C4221V (1K – m),
Table 1. Writing the Offset Registers
LD WEN
WCLK[1]
Selection
0
0
Empty Offset (LSB)
Empty Offset (MSB)
Full Offset (LSB)
Full Offset (MSB)
CY7C4231V (2K
– m), CY7C4241V (4K – m), and
CY7C4251V (8K – m). PAF is set HIGH by the LOW-to-HIGH
transition of WCLK when the number of available memory
locations is greater than m.
0
1
1
0
1
No Operation
Write Into FIFO
No Operation
1
Note:
1. The same selection sequence applies to reading from the registers. REN1 and REN2 are enabled and a read is performed on the LOW-to-HIGH transition of RCLK.
Document #: 38-06010 Rev. *B
Page 4 of 18
CY7C4421V/4201V/4211V/4221V
CY7C4231V/4241V/4251V
Table 2. Status Flags
Number of Words in FIFO
CY7C4201V
CY7C4421V
0
1 to n[2]
CY7C4211V
FF
H
H
H
H
H
L
PAF
H
PAE
L
EF
L
0
0
1 to n[2]
1 to n[2]
H
L
H
H
H
H
H
(n+1) to 32
33 to (64−(m+1))
(64−m)[3] to 63
64
(n+1) to 128
129 to (256−(m+1))
(256−m)[3] to 255
256
(n+1) to 256
257 to (512−(m+1))
(512−m)[3] to 511
512
H
H
H
H
L
H
L
H
Number of Words in FIFO
CY7C4221V
0
1 to n[2]
CY7C4231V
CY7C4241V
CY7C4251V
FF PAF PAE
EF
L
0
0
0
H
H
H
H
H
L
H
H
H
H
L
L
L
1 to n[2]
1 to n[2]
1 to n[2]
H
H
H
H
H
(n+1) to 512
(n+1) to 1024
(n+1) to 2048
(n+1) to 4096
H
H
H
H
513 to (1024 −(m+1)) 1025 to (2048 −(m+1)) 2049 to (4096 −(m+1)) 4097 to (8192 −(m+1))
(1024−m)[3] to 1023
(2048−m)[3] to 2047
(4096−m)[3] to 4095
(8192−m)[3] to 8191
1024
2048
4096
8192
L
Width Expansion Configuration
Flag Operation
Word width may be increased simply by connecting the corre-
sponding input control signals of multiple devices. A
composite flag should be created for each of the end-point
status flags (EF and FF). The partial status flags (PAE and
PAF) can be detected from any one device. Figure 2 demon-
strates a 18-bit word width by using two CY7C42X1Vs. Any
word width can be attained by adding additional
CY7C42X1Vs.
The CY7C42X1 devices provide four flag pins to indicate the
condition of the FIFO contents. Empty, Full, PAE, and PAF are
synchronous.
Full Flag
The Full Flag (FF) will go LOW when device is full. Write opera-
tions are inhibited whenever FF is LOW regardless of the state
of WEN1 and WEN2/LD. FF is synchronized to WCLK, i.e., it
is exclusively updated by each rising edge of WCLK.
When the CY7C42X1V is in a Width Expansion Configuration,
the Read Enable (REN2) control input can be grounded (see
Figure 2). In this configuration, the Write Enable 2/Load
(WEN2/LD) pin is set to LOW at Reset so that the pin operates
as a control to load and read the programmable flag offsets.
Empty Flag
The Empty Flag (EF) will go LOW when the device is empty.
Read operations are inhibited whenever EF is LOW,
regardless of the state of REN1 and REN2. EF is synchronized
to RCLK, i.e., it is exclusively updated by each rising edge of
RCLK.
Notes:
2. n = Empty Offset (n=7 default value).
3. m = Full Offset (m=7 default value).
Document #: 38-06010 Rev. *B
Page 5 of 18
CY7C4421V/4201V/4211V/4221V
CY7C4231V/4241V/4251V
RESET(RS)
RESET(RS)
DATAIN (D)
18
9
9
READ CLOCK(RCLK)
WRITE CLOCK(WCLK)
READ ENABLE1 (REN1)
WRITE ENABLE1 (WEN1)
OUTPUT ENABLE (OE)
PROGRAMMABLE (PAE)
WRITE ENABLE2/LOAD
(WEN2/LD)
EMPTY FLAG (EF) #1
CY7C42X1V
CY7C42X1V
PROGRAMMABLE (PAF)
FULL FLAG (FF) # 1
EF
EMPTY FLAG (EF) #2
DATA OUT (Q)
EF
FF
FF
9
18
FULL FLAG (FF) # 2
9
Read Enable 2 (REN2)
Read Enable 2 (REN2)
Figure 2. Block Diagram of 64 x 9, 256 x 9, 512 x 9, 1024 x 9, 2048 x 9, 4096 x 9, 8192 x 9 Low-Voltage Synchronous FIFO
Memory Used in a Width-Expansion Configuration
Document #: 38-06010 Rev. *B
Page 6 of 18
CY7C4421V/4201V/4211V/4221V
CY7C4231V/4241V/4251V
Output Current into Outputs (LOW)............................. 20 mA
Maximum Ratings
Static Discharge Voltage...........................................> 2001V
(per MIL-STD-883, Method 3015)
(Above which the useful life may be impaired. For user guide-
lines, not tested.)
Latch-up Current.....................................................> 200 mA
Storage Temperature ...................................–65°C to +150°C
Operating Range
Ambient Temperature with
Power Applied............................................. –-55°C to +125°C
Range
Commercial
Industrial
Ambient Temperature
0°C to +70°C
VCC
Supply Voltage to Ground Potential............... –0.5V to +5.0V
3.3V ± 300 mV
3.3V ± 300 mV
DC Voltage Applied to Outputs
in High-Z State ............................................... –0.5V to +5.0V
–40° to +85°C
DC Input Voltage............................................ –0.5V to +5.0V
Electrical Characteristics Over the Operating Range
7C42X1V-15
7C42X1V-25
7C42X1V-35
Parameter
Description
Test Conditions
VCC = Min.,
OH = −2.0 mA
Min.
Max.
Min.
Max.
Min.
Max.
Unit
VOH
Output HIGH Voltage
2.4
2.4
2.4
V
I
VOL
Output LOW Voltage
VCC = Min.,
IOL = 8.0 mA
0.4
0.4
0.4
V
VIH
VIL
IIX
Input HIGH Voltage
Input LOW Voltage
2.0
−0.5
−10
−10
5.0
0.8
2.0
−0.5
−10
−10
5.0
0.8
2.0
−0.5
−10
−10
5.0
0.8
V
V
Input Leakage Current VCC = Max.
+10
+10
+10
+10
+10
+10
µA
µA
IOZL
IOZH
Output OFF, High Z
Current
OE > VIH,
SS < VO < VCC
V
[4]
ICC
Active Power Supply
Current
Com’l
20
6
20
6
20
6
mA
mA
[5]
ISB
Average Standby
Current
Com’l
Capacitance[6]
Parameter
Description
Input Capacitance
Output Capacitance
Test Conditions
TA = 25°C, f = 1 MHz,
CC = 5.0V
Max.
Unit
CIN
5
7
pF
pF
V
COUT
AC Test Loads and Waveforms[7, 8]
R1 = 330Ω
3.3V
ALL INPUT PULSES
OUTPUT
3.0V
GND
90%
10%
90%
10%
R2 = 510Ω
C
L
≤ 3 ns
≤ 3 ns
INCLUDING
JIG AND
SCOPE
Equivalent to:
THÉVENIN EQUIVALENT
Rth = 200Ω
OUTPUT
Vth = 2.0V
Notes:
4. Outputs open. Tested at Frequency = 20 MHz.
5. All inputs = V – 0.2V, except WCLK and RCLK, which are switching at 20 MHz.
CC
6. Tested initially and after any design or process changes that may affect these parameters.
7. C = 30 pF for all AC parameters except for t
.
OHZ
L
8. C = 5 pF for t
.
L
OHZ
Document #: 38-06010 Rev. *B
Page 7 of 18
CY7C4421V/4201V/4211V/4221V
CY7C4231V/4241V/4251V
Switching Characteristics Over the Operating Range
7C42X1V-15
7C42X1V-25
7C42X1V-35
Parameter
tS
Description
Clock Cycle Frequency
Min.
Max.
66.7
11
Min.
Max.
40
Min.
Max.
28.6
20
Unit
MHz
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
tA
Data Access Time
2
15
6
2
25
10
10
6
15
2
35
14
14
7
tCLK
tCLKH
tCLKL
tDS
Clock Cycle Time
Clock HIGH Time
Clock LOW Time
6
Data Set-Up Time
4
tDH
Data Hold Time
1
2
2
tENS
tENH
tRS
Enable Set-Up Time
4
6
7
Enable Hold Time
Reset Pulse Width[9]
1
2
2
15
10
10
25
15
15
35
20
20
tRSS
tRSR
tRSF
tOLZ
tOE
Reset Set-Up Time
Reset Recovery Time
Reset to Flag and Output Time
Output Enable to Output in Low Z[10]
Output Enable to Output Valid
Output Enable to Output in High Z[10]
Write Clock to Full Flag
Read Clock to Empty Flag
Clock to Programmable Almost-Full Flag
Clock to Programmable Almost-Full Flag
18
25
35
0
3
3
0
3
3
0
3
3
8
12
12
15
15
22
22
15
15
20
20
25
25
tOHZ
tWFF
tREF
tPAF
tPAE
tSKEW1
8
11
11
16
16
Skew Time between Read Clock and Write Clock
for Empty Flag and Full Flag
6
10
18
12
20
tSKEW2
Skew Time between Read Clock and Write Clock
for Almost-Empty Flag and Almost-Full Flag
15
ns
Notes:
9. Pulse widths less than minimum values are not allowed.
10. Values guaranteed by design, not currently tested.
Document #: 38-06010 Rev. *B
Page 8 of 18
CY7C4421V/4201V/4211V/4221V
CY7C4231V/4241V/4251V
Switching Waveforms
Write Cycle Timing
t
CLK
t
t
CLKL
CLKH
WCLK
t
t
DH
DS
D –D
0
8
t
ENH
t
ENS
WEN1
NO OPERATION
NO OPERATION
WEN2
t
t
WFF
(if applicable)
WFF
FF
[11]
t
SKEW1
RCLK
REN1,REN2
Read Cycle Timing
t
CKL
t
t
CLKL
CLKH
RCLK
t
t
ENH
ENS
REN1,REN2
EF
NO OPERATION
t
REF
t
REF
t
A
VALID DATA
Q –Q
0
8
t
OLZ
t
OHZ
t
OE
OE
[12]
t
SKEW1
WCLK
WEN1
WEN2
Notes:
11. t
is the minimum time between a rising RCLK edge and a rising WCLK edge to guarantee that FF will go HIGH during the current clock cycle. If the time
SKEW1
between the rising edge of RCLK and the rising edge of WCLK is less than t
, then FF may not change state until the next WCLK rising edge.
SKEW1
12. t
is the minimum time between a rising WCLK edge and a rising RCLK edge to guarantee that EF will go HIGH during the current clock cycle. It the time
SKEW1
between the rising edge of WCLK and the rising edge of RCLK is less than t
, then EF may not change state until the next RCLK rising edge.
SKEW1
Document #: 38-06010 Rev. *B
Page 9 of 18
CY7C4421V/4201V/4211V/4221V
CY7C4231V/4241V/4251V
Switching Waveforms (continued)
Reset Timing[13]
t
RS
RS
t
t
t
RSR
RSS
REN1,
REN2
t
RSR
RSS
WEN1
t
t
RSR
RSS
[15]
WEN2/LD
t
t
t
RSF
RSF
RSF
EF,PAE
FF,PAF,
O =1 [14]
E
Q
Q
8
0 −
OE=0
Notes:
13. The clocks (RCLK, WCLK) can be free-running during reset.
14. After reset, the outputs will be LOW if OE = 0 and three-state if OE=1.
15. Holding WEN2/LD HIGH during reset will make the pin act as a second enable pin. Holding WEN2/LD LOW during reset will make the pin act as a load enable
for the programmable flag offset registers.
Document #: 38-06010 Rev. *B
Page 10 of 18
CY7C4421V/4201V/4211V/4221V
CY7C4231V/4241V/4251V
Switching Waveforms (continued)
First Data Word Latency after Reset with Simultaneous Read and Write
WCLK
t
DS
D –D
D
0
(FIRSTVALIDWRITE)
D
1
D
2
D
3
D
4
0
8
t
ENS
[16]
t
WEN1
FRL
WEN2
(if applicable)
t
SKEW1
RCLK
EF
t
REF
[17]
t
A
t
A
REN1,
REN2
Q –Q
D
0
D
1
0
8
t
OLZ
t
OE
OE
Notes:
16. When t
> minimum specification, t
(maximum) = t
+ t
. When t
< minimum specification, t
(maximum) = either 2*t
+ t
or t
SKEW1 CLK
SKEW1
FRL
CLK
SKEW1
SKEW1
FRL
CLK
+ t
. The Latency Timing applies only at the Empty Boundary (EF = LOW).
SKEW1
17. The first word is available the cycle after EF goes HIGH, always.
Document #: 38-06010 Rev. *B
Page 11 of 18
CY7C4421V/4201V/4211V/4221V
CY7C4231V/4241V/4251V
Switching Waveforms (continued)
Empty Flag Timing
WCLK
t
t
DS
DS
DATAWRITE2
DATAWRITE1
D –D
0
8
t
t
ENH
ENH
t
ENS
WEN1
t
t
ENS
t
t
ENS
ENH
ENH
t
ENS
WEN2
(if applicable)
[16]
[16]
t
t
FRL
FRL
RCLK
t
t
t
REF
t
t
SKEW1
REF
REF
SKEW1
EF
REN1,
REN2
LOW
OE
t
A
DATA IN OUTPUT REGISTER
DATA READ
Q –Q
0
8
Document #: 38-06010 Rev. *B
Page 12 of 18
CY7C4421V/4201V/4211V/4221V
CY7C4231V/4241V/4251V
Switching Waveforms (continued)
Full Flag Timing
NO WRITE
NO WRITE
NO WRITE
WCLK
[11]
[11]
t
t
DATA WRITE
t
SKEW1
DS
SKEW1
DATA WRITE
D –D
0
8
t
t
t
WFF
WFF
WFF
FF
WEN1
WEN2
(if applicable)
RCLK
t
t
ENH
ENH
t
t
ENS
ENS
REN1,
REN2
LOW
OE
t
A
t
A
DATA READ
NEXT DATA READ
DATA IN OUTPUT REGISTER
Q –Q
0
8
Programmable Almost Empty Flag Timing
t
t
CLKL
CLKH
WCLK
t
t
t
ENS
ENH
WEN1
WEN2
(if applicable)
t
ENS
[18]
ENH
Note 19
PAE
N + 1 WORDS
INFIFO
Note 20
t
PAE
t
t
PAE
SKEW2
RCLK
t
ENS
t
t
ENH
ENS
REN1,
REN2
Notes:
18. t
is the minimum time between a rising WCLK and a rising RCLK edge for PAE to change state during that clock cycle. If the time between the edge of
SKEW2
WCLK and the rising RCLK is less than t
, then PAE may not change state until the next RCLK.
SKEW2
19. PAE offset = n.
20. If a read is performed on this rising edge of the read clock, there will be Empty + (n−1) words in the FIFO when PAE goes LOW.
Document #: 38-06010 Rev. *B
Page 13 of 18
CY7C4421V/4201V/4211V/4221V
CY7C4231V/4241V/4251V
Switching Waveforms (continued)
Programmable Almost Full Flag Timing
Note 21
t
t
CLKL
CLKH
WCLK
t
t
t
ENS
ENH
WEN1
[22]
WEN2
(if applicable)
t
t
PAF
ENS
ENH
FULL − M WORDS
IN FIFO [23]
PAF
FULL − (M+1) WORDS
IN FIFO
[24]
t
t
PAF
SKEW2
RCLK
t
ENS
t
t
ENH
ENS
REN1,
REN2
Write Programmable Registers
t
CLK
t
t
CLKL
CLKH
WCLK
t
t
ENS
ENH
WEN2/LD
t
ENS
WEN1
t
t
DH
DS
D –D
0
8
PAE OFFSET
LSB
PAE OFFSET
MSB
PAF OFFSET
LSB
PAF OFFSET
MSB
Notes:
21. If a write is performed on this rising edge of the write clock, there will be Full – (m–1) words of the FIFO when PAF goes LOW.
22. PAF offset = m.
23. 64–m words for CY7C4421V, 256-m words in FIFO for CY7C4201V, 512–m words for CY7C4211V, 1024–m words for CY7C4221V, 2048–m words for
CY7C4231V, 4096–m words for CY7C4241V, 8192–m words for CY7C4251V.
24. t
is the minimum time between a rising RCLK edge and a rising WCLK edge for PAF to change during that clock cycle. If the time between the rising edge
SKEW2
of RCLK and the rising edge of WCLK is less than t
, then PAF may not change state until the next WCLK.
SKEW2
Document #: 38-06010 Rev. *B
Page 14 of 18
CY7C4421V/4201V/4211V/4221V
CY7C4231V/4241V/4251V
Switching Waveforms (continued)
Read Programmable Registers
t
CLK
t
t
CLKL
CLKH
RCLK
t
t
ENS
ENH
WEN2/LD
t
ENS
PAF OFFSET
MSB
REN1,
REN2
t
A
PAF OFFSET
LSB
UNKNOWN
PAE OFFSET LSB
PAE OFFSET MSB
Q –Q
0
8
Ordering Information
256 x 9 Low Voltage Synchronous FIFO
Speed (ns)
Ordering Code
CY7C4201V-15AC
CY7C4201V-15AXC
CY7C4201V-25AC
Package Name
Package Type
32-Lead Thin Quad Flatpack
Operating Range
15
A32
A32
A32
Commercial
32-Lead Pb-Free Thin Quad Flatpack
32-Lead Thin Quad Flatpack
25
Commercial
512 x 9 Low Voltage Synchronous FIFO
Speed (ns)
Ordering Code
CY7C4211V-15AC
CY7C4211V-15JC
CY7C4211V-15AI
CY7C4211V-15AXI
CY7C4211V-25AC
CY7C4211V-25JC
Package Name
Package Type
32-Lead Thin Quad Flatpack
Operating Range
15
A32
J65
A32
A32
A32
J65
Commercial
32-Lead Plastic Leaded Chip Carrier
32-Lead Thin Quad Flatpack
Industrial
32-Lead Pb-Free Thin Quad Flatpack
32-Lead Thin Quad Flatpack
25
Commercial
32-Lead Plastic Leaded Chip Carrier
1K x 9 Low Voltage Synchronous FIFO
Speed (ns)
Ordering Code
CY7C4221V-15AC
CY7C4221V-15JC
CY7C4221V-25AC
Package Name
Package Type
32-Lead Thin Quad Flatpack
32-Lead Plastic Leaded Chip Carrier
32-Lead Thin Quad Flatpack
Operating Range
15
A32
J65
A32
Commercial
25
Commercial
2K x 9 Low Voltage Synchronous FIFO
Speed (ns)
Ordering Code
CY7C4231V-15AC
CY7C4231V-15JXC
CY7C4231V-15JC
CY7C4231V-25AXC
CY7C4231V-25AC
CY7C4231V-25JC
Package Name
Package Type
Operating Range
15
A32
J65
J65
A32
A32
J65
32-Lead Thin Quad Flatpack
Commercial
32-Lead Pb-Free Plastic Leaded Chip Carrier
32-Lead Plastic Leaded Chip Carrier
32-Lead Pb-Free Thin Quad Flatpack
32-Lead Thin Quad Flatpack
25
Commercial
32-Lead Plastic Leaded Chip Carrier
Document #: 38-06010 Rev. *B
Page 15 of 18
CY7C4421V/4201V/4211V/4221V
CY7C4231V/4241V/4251V
Ordering Information (continued)
4K x 9 Low Voltage Synchronous FIFO
Speed (ns)
Ordering Code
CY7C4241V-15AC
CY7C4241V-15AXC
CY7C4241V-15JXC
CY7C4241V-15JC
CY7C4241V-25AC
CY7C4241V-25AXC
CY7C4241V-25JC
Package Name
Package Type
Operating Range
15
A32
A32
J65
J65
A32
A32
J65
32-Lead Thin Quad Flatpack
Commercial
32-Lead Pb-Free Thin Quad Flatpack
32-Lead Pb-Free Plastic Leaded Chip Carrier
32-Lead Plastic Leaded Chip Carrier
32-Lead Thin Quad Flatpack
25
Commercial
32-Lead Pb-Free Thin Quad Flatpack
32-Lead Plastic Leaded Chip Carrier
8K x 9 Low Voltage Synchronous FIFO
Speed (ns)
Ordering Code
CY7C4251V-15AC
CY7C4251V-15AXC
CY7C4251V-15JC
CY7C4251V-25AC
CY7C4251V-25AXC
Package Name
Package Type
32-Lead Thin Quad Flatpack
Operating Range
15
A32
A32
J65
A32
A32
Commercial
32-Lead Pb-Free Thin Quad Flatpack
32-Lead Plastic Leaded Chip Carrier
32-Lead Thin Quad Flatpack
25
Commercial
32-Lead Pb-Free Thin Quad Flatpack
Package Diagrams
32-Lead Thin Plastic Quad Flatpack 7 x 7 x 1.0 mm A32
32-Lead Pb-Free Thin Plastic Quad Flatpack 7 x 7 x 1.0 mm A32
51-85063-*B
Document #: 38-06010 Rev. *B
Page 16 of 18
CY7C4421V/4201V/4211V/4221V
CY7C4231V/4241V/4251V
Package Diagrams (continued)
32-Lead Plastic Leaded Chip Carrier J65
32-Lead Pb-Free Plastic Leaded Chip Carrier J65
51-85002-*B
All product and company names mentioned in this document are the trademarks of their respective holders.
Document #: 38-06010 Rev. *B
Page 17 of 18
© Cypress Semiconductor Corporation, 2005. The information contained herein is subject to change without notice. Cypress Semiconductor Corporation assumes no responsibility for the use
of any circuitry other than circuitry embodied in a Cypress product. Nor does it convey or imply any license under patent or other rights. Cypress products are not warranted nor intended to be
used for medical, life support, life saving, critical control or safety applications, unless pursuant to an express written agreement with Cypress. Furthermore, Cypress does not authorize its
products for use as critical components in life-support systems where a malfunction or failure may reasonably be expected to result in significant injury to the user. The inclusion of Cypress
products in life-support systems application implies that the manufacturer assumes all risk of such use and in doing so indemnifies Cypress against all charges.
CY7C4421V/4201V/4211V/4221V
CY7C4231V/4241V/4251V
Document History Page
Document Title: CY7C4421V/4201V/4211V/4221V/CY7C4231V/4241V/4251V Low-Voltage 64/256/512/1K/2K/4K/8K x 9
Synchronous FIFOs
Document Number: 38-06010
Orig. of
REV.
ECN NO. Issue Date Change
Description of Change
**
106471
127857
09/10/01
08/25/03
SZV
FSG
Change from Spec number: 38-00622 to 38-06010
*A
Fixed empty flag timing diagram
Fixed switching waveform diagram typo
*B
384573
See ECN ESH
Added Pb-Free logo to top of front page
Inserted industrial temperature range into operating range
Added parts CY7C4251V-25AXC, CY7C4251V-15AXC,
CY7C4241V-15AXC, CY7C4241V-15JXC, CY7C4241V-25XC,
CY7C4231V-25AXC, CY7C4221V-15AI, CY7C4211V-15AXI,
CY7C4201V-15AXC to ordering information.
Document #: 38-06010 Rev. *B
Page 18 of 18
相关型号:
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