3.3V 64K/128K x 8/9
Dual-Port Static RAM
CY7C008V/009V
CY7C018V/019V
Cypress Semiconductor Corporation 198 Champion Court San Jose,CA 95134-1709 408-943-2600
Document #: 38-06044 Rev. *C Revised September 6, 2005
Features
True Dual-Ported memory cells which allow simulta-
neous access of the same memory location
64K x 8 organization (CY7C008)
128K x 8 organization (CY7C009)
64K x 9 organization (CY7C018)
128K x 9 organization (CY7C019)
0.35-micron CMOS for optimum speed/power
High-speed access: 15/20/25 ns
Low operating power
Active: ICC = 115 mA (typical)
Standby: ISB3 = 10 µA (typical)
Fully asynchronous operation
Automatic power-down
Expandable data bus to 16/18 bits or more using
Master/Slave chip select when using more than one
device
On-chip arbitration logic
Semaphores included to permit software handshaking
between ports
•INT
flag for port-to-port communication
Dual Chip Enables
Pin select for Master or Slave
Commercial and Industrial Temperature Ranges
Available in 100-pin TQFP
Pb-Free packages available
Notes:
1. I/O0–I/O7 for x8 devices; I/O0–I/O8 for x9 devices.
2. A0–A15 for 64K devices; A0–A16 for 128K.
3. BUSY is an output in master mode and an input in slave mode.
I/O
Control
Address
Decode
A0L–A15/16L
CEL
OEL
R/WL
BUSYL
I/O
Control
Interrupt
Semaphore
Arbitration
SEML
INTL
M/S
Logic Block Diagram
A0L–A15/16L
True Dual-Ported
RAM Array
A0R–A15/16R
CER
OER
R/WR
BUSYR
SEMR
INTR
Address
Decode A0R–A15/16R
[1] [1]
[2] [2]
[3] [3]
[2] [2]
R/WL
CE0L
CE1L
OEL
I/O0L–I/O7/8L
CEL
R/WR
CE0R
CE1R
OER
I/O0R–I/O7/8R
CER
16/17
8/9
16/17
8/9
16/17 16/17
CY7C008V CY7C018V CY7C009V CY7C019V 3.3V 64K/128K x 8/9
Dual-Port Static RAM
[+] Feedback
CY7C008V/009V
CY7C018V/019V
Document #: 38-06044 Rev. *C Page 2 of 18
Functional Description
The CY7C008V/009V and CY7018V/019V are low-power
CMOS 64K, 128K x 8/9 dual-port static RAMs. Various
arbitration schemes are included on the devices to handle
situations when multiple processors access the same piece of
data. Two ports are provided permitting independent,
asynchronous access for reads and writes to any location in
memory. The devices can be utilized as standalone 8/9-bit
dual-port static RAMs or multiple devices can be combined in
order to function as a 16/18-bit or wider master/slave dual-port
static RAM. An M/S pin is provided for implementing 16/18-bit
or wider memory applications without the need for separate
master and slave devices or additional discrete logic. Appli-
cation areas include interprocessor/multiprocessor designs,
communications status buffering, and dual-port
video/graphics memory.
Each port has independent control pins: chip enable (CE),
read or write enable (R/W), and output enable (OE). Two flags
are provided on each port (BUSY and INT). BUSY signals that
the port is trying to access the same location currently being
accessed by the other port. The interrupt flag (INT) permits
communication between ports or systems by means of a mail
box. The semaphores are used to pass a flag, or token, from
one port to the other to indicate that a shared resource is in
use. The semaphore logic is comprised of eight shared
latches. Only one side can control the latch (semaphore) at
any time. Control of a semaphore indicates that a shared
resource is in use. An automatic power-down feature is
controlled independently on each port by a chip select (CE)
pin.
The CY7C008V/009V and CY7018V/019V are available in
100-pin Thin Quad Plastic Flatpacks (TQFP).
Pin Configurations
Note:
4. This pin is NC for CY7C008V.
1
3
2
92 91 90 848587 868889 83 82 81 7678 77798093949596979899100
59
60
61
67
66
64
65
63
62
68
69
70
75
73
74
72
71
NC
NC
A7R
A8R
A9R
A10R
A15R
A12R
A14R
GND
NC
NC
CE0R
A13R
A11R
NC
NC
CE1R
SEMR
R/WR
OER
GND
GND
NC
A16R
58
57
56
55
54
53
52
51
CY7C008V (64K x 8)
NC
NC
A7L
A8L
A9L
A10L
A15L
A12L
A14L
VCC
NC
NC
CE0L
A13L
A11L
NC
NC
CE1L
SEML
R/WL
OEL
GND
NC
NC
A16L
17
16
15
9
10
12
11
13
14
8
7
6
4
5
18
19
20
21
22
23
24
25
NC
NC
A6L
A5L
A4L
A3L
INTL
A1L
NC
GND
M/S
A0R
A1R
A0L
A2L
BUSYR
INTR
A2R
A3R
A4R
A5R
A6R
NC
NC
BUSYL
34 35 36 424139 403837 43 44 45 5048 494746
NC
NC
NC
I/O7R
I/O6R
I/O5R
I/01R
I/O3R
I/O2R
GND
VCC
GND
I/O2L
VCC
I/O4R
I/O0L
I/O1L
I/O3L
I/O4L
I/O5L
I/O6L
I/O7L
NC
GND
I/O0R
3332313029282726
CY7C009V (128K x 8)
100-Pin TQFP
(Top View)
[4][4]
[+] Feedback
CY7C008V/009V
CY7C018V/019V
Document #: 38-06044 Rev. *C Page 3 of 18
Pin Configurations (continued)
Note:
5. This pin is NC for CY7C018V.
Selection Guide
CY7C008V/009V
CY7C018V/019V
-15
CY7C008V/009V
CY7C018V/019V
-20
CY7C008V/009V
CY7C018V/019V
-25 Unit
Maximum Access Time 15 20 25 ns
Typical Operating Current 125 120 115 mA
Typical Standby Current for ISB1
(Both ports TTL level)
35 35 30 mA
Typical Standby Current for ISB3
(Both ports CMOS level)
10 µA 10 µA10 µAµA
1
3
2
92 91 90 848587 868889 83 82 81 7678 77798093949596979899100
59
60
61
67
66
64
65
63
62
68
69
70
75
73
74
72
71
NC
NC
A7R
A8R
A9R
A10R
A15R
A12R
A14R
GND
NC
NC
CE0R
A13R
A11R
NC
NC
CE1R
SEMR
R/WR
OER
GND
GND
NC
A16R
58
57
56
55
54
53
52
51
CY7C018V (64K x 9)
NC
NC
A7L
A8L
A9L
A10L
A15L
A12L
A14L
VCC
NC
NC
CE0L
A13L
A11L
NC
NC
CE1L
SEML
R/WL
OEL
GND
NC
NC
A16L
17
16
15
9
10
12
11
13
14
8
7
6
4
5
18
19
20
21
22
23
24
25
NC
NC
A6L
A5L
A4L
A3L
BUSYL
A1L
INTL
GND
VCC
INTR
A0R
A0L
A2L
M/S
BUSYR
A1R
A2R
A3R
A4R
A5R
A6R
NC
GND
34 35 36 424139 403837 43 44 45 5048 494746
NC
NC
I/O8R
I/O7R
I/O6R
I/O5R
I/01R
I/O3R
I/O2R
GND
VCC
GND
I/O2L
VCC
I/O4R
I/O0L
I/O1L
I/O3L
I/O4L
I/O5L
I/O6L
I/O7L
I/O8L
GND
I/O0R
3332313029282726
CY7C019V (128K x 9)
100-Pin TQFP
(Top View)
[5]
[5]
[+] Feedback
CY7C008V/009V
CY7C018V/019V
Document #: 38-06044 Rev. *C Page 4 of 18
Maximum Ratings[6]
(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 ............... –0.5V to +4.6V
DC Voltage Applied to
Outputs in High Z State............................–0.5V to VCC+0.5V
DC Input Voltage ..................................... –0.5V to VCC+0.5V
Output Current into Outputs (LOW)............................. 20 mA
Static Discharge Voltage........................................... >1100V
Latch-Up Current.................................................... >200 mA
Notes:
6. The Voltage on any input or I/O pin cannot exceed the power pin during power-up.
7. Industrial parts are available in CY7C009V and CY7C019V only.
Pin Definitions
Left Port Right Port Description
CE0L, CE1L CER, CE1R Chip Enable (CE is LOW when CE0VIL and CE1 VIH)
R/WLR/WRRead/Write Enable
OELOEROutput Enable
A0L–A16L A0R–A16R Address (A0–A15 for 64K devices and A0–A16 for 128K devices)
I/O0L–I/O8L I/O0R–I/O8R Data Bus Input/Output (I/O0–I/O7 for x8 devices and I/O0–I/O8 for x9)
SEML SEMRSemaphore Enable
INTLINTRInterrupt Flag
BUSYLBUSYRBusy Flag
M/S Master or Slave Select
VCC Power
GND Ground
NC No Connect
Operating Range
Range
Ambient
Temperature VCC
Commercial 0°C to +70°C 3.3V ± 300 mV
Industrial[7] –40°C to +85°C 3.3V ± 300 mV
[+] Feedback
CY7C008V/009V
CY7C018V/019V
Document #: 38-06044 Rev. *C Page 5 of 18
Notes:
8. fMAX = 1/tRC = All inputs cycling at f = 1/tRC (except output enable). f=0 means no address or control lines change. This applies only to inputs at CMOS level
standby ISB3.
9. Tested initially and after any design or process changes that may affect these parameters.
Electrical Characteristics Over the Operating Range
Parameter Description
CY7C008V/009V
CY7C018V/019V
Unit
-15 -20 -25
Min. Typ. Max. Min. Typ. Max. Min. Typ. Max.
VOH Output HIGH Voltage (VCC = Min., IOH = –4.0 mA) 2.4 2.4 2.4 V
VOL Output LOW Voltage (VCC = Min., IOH = +4.0 mA) 0.4 0.4 0.4 V
VIH Input HIGH Voltage 2.2 2.2 2.2 V
VIL Input LOW Voltage 0.8 0.8 0.8 V
IIX Input Leakage Current –5 5 –5 5 –5 5 µA
IOZ Output Leakage Current –10 10 –10 10 –10 10 µA
ICC Operating Current (VCC=Max.
IOUT = 0 mA) Outputs Disabled
Com’l. 125 185 120 175 115 165 mA
Ind.[7] 140 195 mA
ISB1 Standby Current (Both Ports TTL Level)
CEL & CER VIH, f = fMAX
Com’l. 35 50 35 45 30 40 mA
Ind.[7] 45 55 mA
ISB2 Standby Current (One Port TTL Level)
CEL | CER VIH, f = fMAX
Com’l. 80 120 75 110 65 95 mA
Ind.[7] 85 120 mA
ISB3 Standby Current (Both Ports CMOS
Level) CEL & CER VCC 0.2V, f = 0
Com’l. 10 250 10 250 10 250 µA
Ind.[7] 10 250 µA
ISB4 Standby Current (One Port CMOS Level)
CEL | CER VIH, f = fMAX[8] Com’l. 75 105 70 95 60 80 mA
Ind.[7] 80 105 mA
Capacitance[9]
Parameter Description Test Conditions Max. Unit
CIN Input Capacitance TA = 25°C, f = 1 MHz,
VCC = 3.3V
10 pF
COUT Output Capacitance 10 pF
AC Test Loads and Waveforms
3.0V
GND 90% 90%
10%
3ns 3ns
10%
ALL INPUT PULSES
(a) Normal Load (Load 1)
R1 = 590
3.3V
OUTPUT
R2 = 435
C = 30 pF
VTH = 1.4V
OUTPUT
(b) Thévenin Equivalent (Load 1) (c) Three-State Delay (Load 2)
3.3V
OUTPUT
RTH = 250
including scope and jig)
(Used for tLZ, tHZ, tHZWE, & tLZWE
C = 30 pF
C = 5 pF
R1 = 590
R2 = 435
[+] Feedback
CY7C008V/009V
CY7C018V/019V
Document #: 38-06044 Rev. *C Page 6 of 18
Switching Characteristics Over the Operating Range[10]
Parameter Description
CY7C008V/009V
CY7C018V/019V
Unit
-15 -20 -25
Min. Max. Min. Max. Min. Max.
READ CYCLE
tRC Read Cycle Time 15 20 25 ns
tAA Address to Data Valid 15 20 25 ns
tOHA Output Hold From Address Change 3 3 3 ns
tACE[11] CE LOW to Data Valid 15 20 25 ns
tDOE OE LOW to Data Valid 10 12 13 ns
tLZOE[12, 13, 14] OE LOW to Low Z 3 3 3 ns
tHZOE[12, 13, 14] OE HIGH to High Z 10 12 15 ns
tLZCE[12, 13, 14] CE LOW to Low Z 3 3 3 ns
tHZCE[12, 13, 14] CE HIGH to High Z 10 12 15 ns
tPU[14] CE LOW to Power-Up 0 0 0 ns
tPD[14] CE HIGH to Power-Down 15 20 25 ns
tABE[11] Byte Enable Access Time 15 20 25 ns
WRITE CYCLE
tWC Write Cycle Time 15 20 25 ns
tSCE[11] CE LOW to Write End 12 16 20 ns
tAW Address Valid to Write End 12 16 20 ns
tHA Address Hold From Write End 0 0 0 ns
tSA[11] Address Set-Up to Write Start 0 0 0 ns
tPWE Write Pulse Width 12 17 22 ns
tSD Data Set-Up to Write End 10 12 15 ns
tHD Data Hold From Write End 0 0 0 ns
tHZWE[13, 14] R/W LOW to High Z 10 12 15 ns
tLZWE[13, 14] R/W HIGH to Low Z 3 3 3 ns
tWDD[15] Write Pulse to Data Delay 30 40 50 ns
tDDD[15] Write Data Valid to Read Data Valid 25 30 35 ns
BUSY TIMING[16]
tBLA BUSY LOW from Address Match 15 20 20 ns
tBHA BUSY HIGH from Address Mismatch 15 20 20 ns
tBLC BUSY LOW from CE LOW 152020ns
tBHC BUSY HIGH from CE HIGH 15 16 17 ns
tPS Port Set-Up for Priority 5 5 5 ns
tWB R/W HIGH after BUSY (Slave)000ns
Notes:
10. Test conditions assume signal transition time of 3 ns or less, timing reference levels of 1.5V, input pulse levels of 0 to 3.0V, and output loading of the specified
IOI/IOH and 30-pF load capacitance.
11. To access RAM, CE = L, UB = L, SEM = H. To access semaphore, CE = H and SEM = L. Either condition must be valid for the entire tSCE time.
12. At any given temperature and voltage condition for any given device, tHZCE is less than tLZCE and tHZOE is less than tLZOE.
13. Test conditions used are Load 2.
14. This parameter is guaranteed by design, but it is not production tested.For information on port-to-port delay through RAM cells from writing port to reading port,
refer to Read Timing with Busy waveform.
15. For information on port-to-port delay through RAM cells from writing port to reading port, refer to Read Timing with Busy waveform.
16. Test conditions used are Load 1.
[+] Feedback
CY7C008V/009V
CY7C018V/019V
Document #: 38-06044 Rev. *C Page 7 of 18
Data Retention Mode
The CY7C008V/009V and CY7018V/019V are designed with
battery backup in mind. Data retention voltage and supply
current are guaranteed over temperature. The following rules
ensure data retention:
1. Chip enable (CE) must be held HIGH during data retention,
within VCC to VCC – 0.2V.
2. CE must be kept between VCC – 0.2V and 70% of VCC
during the power-up and power-down transitions.
3. The RAM can begin operation >tRC after VCC reaches the
minimum operating voltage (3.0 volts).
Notes:
17. tBDD is a calculated parameter and is the greater of tWDD–tPWE (actual) or tDDD–tSD (actual).
18. CE = VCC, Vin = GND to VCC, TA = 25°C. This parameter is guaranteed but not tested.
tWH R/W HIGH after BUSY HIGH (Slave) 13 15 17 ns
tBDD[17] BUSY HIGH to Data Valid 15 20 25 ns
INTERRUPT TIMING[16]
tINS INT Set Time 15 20 20 ns
tINR INT Reset Time 15 20 20 ns
SEMAPHORE TIMING
tSOP SEM Flag Update Pulse (OE or SEM)10 10 12 ns
tSWRD SEM Flag Write to Read Time 5 5 5 ns
tSPS SEM Flag Contention Window 5 5 5 ns
tSAA SEM Address Access Time 15 20 25 ns
Switching Characteristics Over the Operating Range[10] (continued)
Parameter Description
CY7C008V/009V
CY7C018V/019V
Unit
-15 -20 -25
Min. Max. Min. Max. Min. Max.
Timing
Parameter Test Conditions[18] Max. Unit
ICCDR1 @ VCCDR = 2V 50 µA
Data Retention Mode
3.0V 3.0V
VCC > 2.0V
VCC to VCC 0.2V
VCC
CE
tRC
VIH
[+] Feedback
CY7C008V/009V
CY7C018V/019V
Document #: 38-06044 Rev. *C Page 8 of 18
Switching Waveforms
Notes:
19. R/W is HIGH for read cycles.
20. Device is continuously selected CE = VIL. This waveform cannot be used for semaphore reads.
21. OE = VIL.
22. Address valid prior to or coincident with CE transition LOW.
23. To access RAM, CE = VIL, SEM = VIH. To access semaphore, CE = VIH, SEM = VIL.
tRC
tAA
tOHA
DATA VALIDPREVIOUS DATA VALID
DATA OUT
ADDRESS
tOHA
Read Cycle No.1 (Either Port Address Access)[19, 20, 21]
tACE
tLZOE
tDOE
tHZOE
tHZCE
DATA VALID
tLZCE
tPU tPD
ISB
ICC
DATA OUT
OE
CE
CURRENT
Read Cycle No.2 (Either Port CE/OE Access)[19, 22, 23]
DATA OUT
tRC
ADDRESS
tAA tOHA
CE
tLZCE
tABE
tHZCE
tACE
tLZCE
Read Cycle No. 3 (Either Port)[19, 21, 22, 23]
[+] Feedback
CY7C008V/009V
CY7C018V/019V
Document #: 38-06044 Rev. *C Page 9 of 18
Notes:
24. R/W must be HIGH during all address transitions.
25. A write occurs during the overlap (tSCE or tPWE) of a LOW CE or SEM.
26. tHA is measured from the earlier of CE or R/W or (SEM or R/W) going HIGH at the end of write cycle.
27. If OE is LOW during a R/W controlled write cycle, the write pulse width must be the larger of tPWE or (tHZWE + tSD) to allow the I/O drivers to turn off and data
to be placed on the bus for the required tSD. If OE is HIGH during an R/W controlled write cycle, this requirement does not apply and the write pulse can be
as short as the specified tPWE.
28. To access RAM, CE = VIL, SEM = VIH.
29. Transition is measured ±500 mV from steady state with a 5-pF load (including scope and jig). This parameter is sampled and not 100% tested.
30. During this period, the I/O pins are in the output state, and input signals must not be applied.
31. If the CE or SEM LOW transition occurs simultaneously with or after the R/W LOW transition, the outputs remain in the high-impedance state.
Switching Waveforms (continued)
tAW
tWC
tPWE
tHD
tSD
tHA
CE
R/W
OE
DATA OUT
DATA IN
ADDRESS
tHZOE
tSA
tHZWE tLZWE
Write Cycle No. 1: R/W Controlled Timing[24, 25, 26, 27]
[29]
[29]
[27]
[28]
NOTE 30 NOTE 30
tAW
tWC
tSCE
tHD
tSD
tHA
CE
R/W
DATA IN
ADDRESS
tSA
Write Cycle No. 2: CE Controlled Timing[24, 25, 26, 31]
[28]
[+] Feedback
CY7C008V/009V
CY7C018V/019V
Document #: 38-06044 Rev. *C Page 10 of 18
Notes:
32. CE = HIGH for the duration of the above timing (both write and read cycle).
33. I/O0R = I/O0L = LOW (request semaphore); CER = CEL = HIGH.
34. Semaphores are reset (available to both ports) at cycle start.
35. If tSPS is violated, the semaphore will definitely be obtained by one side or the other, but which side will get the semaphore is unpredictable.
Switching Waveforms (continued)
tSOP
tSAA
VALID ADRESS VALID ADRESS
tHD
DATAIN VALID DATAOUT VALID
tOHA
tAW
tHA
tACE
tSOP
tSCE
tSD
tSA tPWE
tSWRD tDOE
WRITE CYCLE READ CYCLE
OE
R/W
I/O 0
SEM
A0–A2
Semaphore Read After Write Timing, Either Side[32]
MATCH
tSPS
A0L–A2L
MATCH
R/WL
SEML
R/WR
SEMR
Timing Diagram of Semaphore Contention[33, 34, 35]
A0R–A2R
[+] Feedback
CY7C008V/009V
CY7C018V/019V
Document #: 38-06044 Rev. *C Page 11 of 18
Note:
36. CEL = CER = LOW.
Switching Waveforms (continued)
VALID
tDDD
tWDD
MATCH
MATCH
R/WR
DATA INR
DATAOUTL
tWC
ADDRESSR
tPWE
VALID
tSD tHD
ADDRESSL
tPS
tBLA tBHA
tBDD
BUSYL
Timing Diagram of Read with BUSY (M/S=HIGH)[36]
tPWE
R/W
BUSY
tWB tWH
Write Timing with Busy Input (M/S=LOW)
[+] Feedback
CY7C008V/009V
CY7C018V/019V
Document #: 38-06044 Rev. *C Page 12 of 18
Note:
37. If tPS is violated, the busy signal will be asserted on one side or the other, but there is no guarantee to which side BUSY will be asserted.
Switching Waveforms (continued)
ADDRESS MATCH
tPS
tBLC tBHC
ADDRESS MATCH
tPS
tBLC tBHC
CER Valid First:
ADDRESSL,R
BUSYR
CEL
CER
BUSYL
CER
CEL
ADDRESSL,R
Busy Timing Diagram No. 1 (CE Arbitration)[37]
CEL Valid First:
ADDRESS MATCH
tPS
ADDRESSL
BUSYR
ADDRESS MISMATCH
tRC or tWC
tBLA tBHA
ADDRESSR
ADDRESS MATCH ADDRESS MISMATCH
tPS
ADDRESSL
BUSYL
tRC or tWC
tBLA tBHA
ADDRESSR
Right Address Valid First:
Busy Timing Diagram No. 2 (Address Arbitration)
[37]
Left Address Valid First:
[+] Feedback
CY7C008V/009V
CY7C018V/019V
Document #: 38-06044 Rev. *C Page 13 of 18
Notes:
38. tHA depends on which enable pin (CEL or R/WL) is deasserted first.
39. tINS or tINR depends on which enable pin (CEL or R/WL) is asserted last.
Switching Waveforms (continued)
Interrupt Timing Diagrams
WRITE FFFF (1FFFF for CY7C009V/19V)
tWC
Right Side Clears INTR:
tHA
READ FFFF
tRC
tINR
WRITE FFFE (1FFFF for CY7C009V/19V)
tWC
Left Side Sets INTR:
READ 1FFE
tINR
tRC
ADDRESSR
CEL
R/WL
INTL
OEL
ADDRESSR
R/WR
CER
INTL
ADDRESSR
CER
R/WR
INTR
OER
ADDRESSL
R/WL
CEL
INTR
tINS
tHA
tINS
(1FFFF for CY7C009V/19V)
(1FFFF for CY7C009V/19V)
[38]
[39]
[39]
[39]
[38]
[39]
Right Side Sets INTL:
Right Side Clears INTL:
[+] Feedback
CY7C008V/009V
CY7C018V/019V
Document #: 38-06044 Rev. *C Page 14 of 18
Architecture
The CY7C008V/009V and CY7018V/019V consist of an array
of 64K and 128K words of 8 and 9 bits each of dual-port RAM
cells, I/O and address lines, and control signals (CE, OE,
R/W). These control pins permit independent access for reads
or writes to any location in memory. To handle simultaneous
writes/reads to the same location, a BUSY pin is provided on
each port. Two interrupt (INT) pins can be utilized for
port-to-port communication. Two semaphore (SEM) control
pins are used for allocating shared resources. With the M/S
pin, the devices can function as a master (BUSY pins are
outputs) or as a slave (BUSY pins are inputs). The devices
also have an automatic power-down feature controlled by CE.
Each port is provided with its own output enable control (OE),
which allows data to be read from the device.
Functional Description
Write Operation
Data must be set up for a duration of tSD before the rising edge
of R/W in order to guarantee a valid write. A write operation is
controlled by either the R/W pin (see Write Cycle No. 1
waveform) or the CE pin (see Write Cycle No. 2 waveform).
Required inputs for non-contention operations are summa-
rized in Ta b l e 1 .
If a location is being written to by one port and the opposite
port attempts to read that location, a port-to-port flowthrough
delay must occur before the data is read on the output;
otherwise the data read is not deterministic. Data will be valid
on the port tDDD after the data is presented on the other port.
Read Operation
When reading the device, the user must assert both the OE
and CE pins. Data will be available tACE after CE or tDOE after
OE is asserted. If the user wishes to access a semaphore flag,
then the SEM pin must be asserted instead of the CE pin, and
OE must also be asserted.
Interrupts
The upper two memory locations may be used for message
passing. The highest memory location (FFFF for the
CY7C008/18, 1FFFF for the CY7C009/19) is the mailbox for
the right port and the second-highest memory location (FFFE
for the CY7C008/18, 1FFFE for the CY7C009/19) is the
mailbox for the left port. When one port writes to the other
port’s mailbox, an interrupt is generated to the owner. The
interrupt is reset when the owner reads the contents of the
mailbox. The message is user defined.
Each port can read the other port’s mailbox without resetting
the interrupt. The active state of the busy signal (to a port)
prevents the port from setting the interrupt to the winning port.
Also, an active busy to a port prevents that port from reading
its own mailbox and, thus, resetting the interrupt to it.
If an application does not require message passing, do not
connect the interrupt pin to the processors interrupt request
input pin.
The operation of the interrupts and their interaction with Busy
are summarized in Table 2.
Busy
The CY7C008V/009V and CY7018V/019V provide on-chip
arbitration to resolve simultaneous memory location access
(contention). If both ports’ CEs are asserted and an address
match occurs within tPS of each other, the busy logic will
determine which port has access. If tPS is violated, one port
will definitely gain permission to the location, but it is not
predictable which port will get that permission. BUSY will be
asserted tBLA after an address match or tBLC after CE is taken
LOW.
Master/Slave
A M/S pin is provided in order to expand the word width by
configuring the device as either a master or a slave. The BUSY
output of the master is connected to the BUSY input of the
slave. This will allow the device to interface to a master device
with no external components. Writing to slave devices must be
delayed until after the BUSY input has settled (tBLC or tBLA),
otherwise, the slave chip may begin a write cycle during a
contention situation. When tied HIGH, the M/S pin allows the
device to be used as a master and, therefore, the BUSY line
is an output. BUSY can then be used to send the arbitration
outcome to a slave.
Semaphore Operation
The CY7C008V/009V and CY7018V/019V provide eight
semaphore latches, which are separate from the dual-port
memory locations. Semaphores are used to reserve resources
that are shared between the two ports.The state of the
semaphore indicates that a resource is in use. For example, if
the left port wants to request a given resource, it sets a latch
by writing a zero to a semaphore location. The left port then
verifies its success in setting the latch by reading it. After
writing to the semaphore, SEM or OE must be deasserted for
tSOP before attempting to read the semaphore. The
semaphore value will be available tSWRD + tDOE after the rising
edge of the semaphore write. If the left port was successful
(reads a zero), it assumes control of the shared resource,
otherwise (reads a one) it assumes the right port has control
and continues to poll the semaphore. When the right side has
relinquished control of the semaphore (by writing a one), the
left side will succeed in gaining control of the semaphore. If the
left side no longer requires the semaphore, a one is written to
cancel its request.
Semaphores are accessed by asserting SEM LOW. The SEM
pin functions as a chip select for the semaphore latches (CE
must remain HIGH during SEM LOW). A0–2 represents the
semaphore address. OE and R/W are used in the same
manner as a normal memory access. When writing or reading
a semaphore, the other address pins have no effect.
When writing to the semaphore, only I/O0 is used. If a zero is
written to the left port of an available semaphore, a one will
appear at the same semaphore address on the right port. That
semaphore can now only be modified by the side showing zero
(the left port in this case). If the left port now relinquishes
control by writing a one to the semaphore, the semaphore will
be set to one for both sides. However, if the right port had
requested the semaphore (written a zero) while the left port
had control, the right port would immediately own the
semaphore as soon as the left port released it. Table 3 shows
sample semaphore operations.
When reading a semaphore, all data lines output the
semaphore value. The read value is latched in an output
[+] Feedback
CY7C008V/009V
CY7C018V/019V
Document #: 38-06044 Rev. *C Page 15 of 18
register to prevent the semaphore from changing state during
a write from the other port. If both ports attempt to access the
semaphore within tSPS of each other, the semaphore will
definitely be obtained by one side or the other, but there is no
guarantee which side will control the semaphore.
Notes:
40. A0L–16L and A0R–16R, 1FFFF/1FFFE for the CY7C009V/19V.
41. If BUSYR = L, then no change.
42. If BUSYL = L, then no change.
Table 1. Non-Contending Read/Write
Inputs Outputs
CE R/W OE SEM I/O0I/O8Operation
H X X H High Z Deselected: Power-Down
H H L L Data Out Read Data in Semaphore Flag
X X H X High Z I/O Lines Disabled
H X L Data In Write into Semaphore Flag
L H L H Data Out Read
L L X H Data In Write
L X X L Not Allowed
Table 2. Interrupt Operation Example (assumes BUSYL = BUSYR = HIGH)[40]
Left Port Right Port
Function R/WLCELOELA0L–16L INTLR/WRCEROERA0R–16R INTR
Set Right INTR Flag L L X FFFF (or 1FFFF) X X X X X L[42]
Reset Right INTR Flag X X X X X X L L FFFF (or 1FFFF) H[41]
Set Left INTL Flag X X X X L[41] L L X FFFE (or 1FFFE) X
Reset Left INTL Flag X L L FFFE (or 1FFFE) H[42] X X X X X
Table 3. Semaphore Operation Example
Function I/O0I/O8 Left I/O0I/O8Right Status
No action 1 1 Semaphore free
Left port writes 0 to semaphore 0 1 Left Port has semaphore token
Right port writes 0 to semaphore 0 1 No change. Right side has no write access to semaphore
Left port writes 1 to semaphore 1 0 Right port obtains semaphore token
Left port writes 0 to semaphore 1 0 No change. Left port has no write access to semaphore
Right port writes 1 to semaphore 0 1 Left port obtains semaphore token
Left port writes 1 to semaphore 1 1 Semaphore free
Right port writes 0 to semaphore 1 0 Right port has semaphore token
Right port writes 1 to semaphore 1 1 Semaphore free
Left port writes 0 to semaphore 0 1 Left port has semaphore token
Left port writes 1 to semaphore 1 1 Semaphore free
[+] Feedback
CY7C008V/009V
CY7C018V/019V
Document #: 38-06044 Rev. *C Page 16 of 18
Ordering Information
64K x8 3.3V Asynchronous Dual-Port SRAM
Speed
(ns) Ordering Code
Package
Name Package Type
Operating
Range
15 CY7C008V-15AC A100 100-Pin Thin Quad Flat Pack Commercial
20 CY7C008V-20AC A100 100-Pin Thin Quad Flat Pack Commercial
25 CY7C008V-25AC A100 100-Pin Thin Quad Flat Pack Commercial
CY7C008V-25AXC A100 100-Pin Pb-Free Thin Quad Flat Pack
64K x9 3.3V Asynchronous Dual-Port SRAM
Speed
(ns) Ordering Code
Package
Name Package Type
Operating
Range
15 CY7C018V-15AC A100 100-Pin Thin Quad Flat Pack Commercial
20 CY7C018V-20AC A100 100-Pin Thin Quad Flat Pack Commercial
25 CY7C018V-25AC A100 100-Pin Thin Quad Flat Pack Commercial
128K x8 3.3V Asynchronous Dual-Port SRAM
Speed
(ns) Ordering Code
Package
Name Package Type
Operating
Range
15 CY7C009V-15AC A100 100-Pin Thin Quad Flat Pack Commercial
CY7C009V-15AXC A100 100-Pin Pb-Free Thin Quad Flat Pack
20 CY7C009V-20AC A100 100-Pin Thin Quad Flat Pack Commercial
CY7C009V-20AI A100 100-Pin Thin Quad Flat Pack Industrial
CY7C009V-20AXI A100 100-Pin Pb-Free Thin Quad Flat Pack
25 CY7C009V-25AC A100 100-Pin Thin Quad Flat Pack Commercial
CY7C009V-25AXC A100 100-Pin Pb-Free Thin Quad Flat Pack
128K x9 3.3V Asynchronous Dual-Port SRAM
Speed
(ns) Ordering Code
Package
Name Package Type
Operating
Range
15 CY7C019V-15AC A100 100-Pin Thin Quad Flat Pack Commercial
CY7C019V-15AXC A100 100-Pin Pb-Free Thin Quad Flat Pack
20 CY7C019V-20AC A100 100-Pin Thin Quad Flat Pack Commercial
CY7C019V-20AXC A100 100-Pin Pb-Free Thin Quad Flat Pack
CY7C019V-20AI A100 100-Pin Thin Quad Flat Pack Industrial
CY7C019V-20AXI A100 100-Pin Pb-Free Thin Quad Flat Pack
25 CY7C019V-25AC A100 100-Pin Thin Quad Flat Pack Commercial
CY7C019V-25AXC A100 100-Pin Pb-Free Thin Quad Flat Pack
[+] Feedback
CY7C008V/009V
CY7C018V/019V
Document #: 38-06044 Rev. *C 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.
All products and company names mentioned in this document may be the trademarks of their respective holders.
Package Diagram
100-Pin Thin Plastic Quad Flat Pack (TQFP) A100
51-85048-*B
100-Pin Pb-Free Thin Plastic Quad Flat Pack (TQFP) A100
[+] Feedback
CY7C008V/009V
CY7C018V/019V
Document #: 38-06044 Rev. *C Page 18 of 18
Document History Page
Document Title: CY7C008V/009V, CY7C018V/019V 3.3V 64K/128K X 8/9 Dual Port Static RAM
Document Number: 38-06044
REV. ECN NO.
Issue
Date
Orig. of
Change Description of Change
** 110192 09/29/01 SZV Change from Spec number: 38-00669 to 38-06044
*A 113541 04/15/02 OOR Change pin 85 from BUSYL to BUSYR (pg. 3)
*B 122294 12/27/02 RBI Power up requirements added to Maximum Ratings Information
*C 393440 See ECN YIM Added Pb-Free Logo
Added Pb-Free parts to ordering information:
CY7C008V-25AXC, CY7C009V-15AXC, CY7C009V-20AXI,
CY7C009V-25AXC, CY7C019V-15AXC, CY7C019V-20AXC,
CY7C019V-20AXI, CY7C019V-25AXC
[+] Feedback