CY7C145-15AC

1CY 7C14 4 fax id: 5205 CY7C145 CY7C144 8K x 8/9 Dual-Port Static RAM with Sem, Int, Busy Features • True Dual-Ported memory cells which allow simultaneous reads of the same memory location • 8K x 8 organization (CY7C144) • 8K x 9 organization (CY7C145) • 0.65-micron CMOS for optimum speed/power • High-speed access: 15ns • Low operating power: ICC = 160 mA (max.) • Fully asynchronous operation • Automatic power-down • TTL compatible • Master/Slave select pin allows bus width expansion to 16/18 bits or more • Busy arbitration scheme provided • Semaphores included to permit software handshaking between ports • INT flag for port-to-port communication • Available in 68-pin PLCC, 64-pin and 80-pin TQFP • Pin compatible and functionally equivalent to IDT7005/IDT7015 are included on the CY7C144/5 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 CY7C144/5 can be utilized as a standalone 64/72-Kbit dual-port static RAM 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. Application 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, BUSY and INT, are provided on each port. 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 enable (CE) pin or SEM pin. Functional Description The CY7C144 and CY7C145 are high-speed CMOS 8K x 8 and 8K x 9 dual-port static RAMs. Various arbitration schemes Logic Block Diagram R/W L CE L OE L R/W R CE R OE R (7C145) I/O8L I/O7L I/O 0L BUSYL [1, 2] I/O CONTROL I/O CONTROL I/O 8R(7C145) I/O 7R I/O 0R BUSY R A 12R [1, 2] A 12L A 0L ADDRESS DECODER MEMORY ARRAY ADDRESS DECODER A 0R CEL OEL R/W L SEM L INT L [2] INTERRUPT SEMAPHORE ARBITRATION CE R OE R R/W R SEM R INT R [2] M/S C144-1 Notes: 1. BUSY is an output in master mode and an input in slave mode. 2. Interrupt: push-pull output and requires no pull-up resistor. Cypress Semiconductor Corporation • 3901 North First Street • San Jose • CA 95134 • 408-943-2600 November 1996 CY7C145 CY7C144 Pin Configurations 68-Pin PLCC Top View 9876 I/O2L I/O3L I/O4L I/O5L GND I/O6L I/O7L VCC GND I/O0R I/O1R I/O2R VCC I/O3R I/O4R I/O5R I/O6R 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 5 4 3 2 1 68 67 66 65 64 63 62 61 60 59 58 57 56 55 54 53 CY7C144/5 52 51 50 49 48 A5L A4L A3L A2L A1L A0L INTL BUSYL GND M/S BUSYR INTR A0R A1R A2R A3R A4R 47 46 45 44 2728 29 30 3132 33 34 35 36 37 38 39 40 41 42 43 C144-2 64-Pin TQFP Top View I/O2L I/O3L I/O4L I/O5L GND I/O6L I/O7L VCC GND I/O0R I/O1R I/O2R VCC I/O3R I/O4R I/O5R 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 CY7C144 48 47 46 45 44 43 42 41 40 39 38 37 36 35 34 33 A4L A3L A2L A1L A0L INTL BUSYL GND M/S BUSYR INTR A0R A1R A2R A3R A4R C144-3 Notes: 3. I/O8R on the CY7C145. 4. I/O8L o n the CY7C145. 2 CY7C145 CY7C144 Pin Configurations (continued) 80-Pin TQFP Top View NC I/O 2L I/O 3L I/O 4L I/O 5L GND I/O 6L I/O 7L V CC NC GND I/O0R I/O1R I/O2R V CC I/O 3R I/O 4R I/O 5R I/O 6R NC 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 CY7C145 60 59 58 57 56 55 54 53 52 51 50 49 48 47 46 45 44 43 42 41 NC A5L A4L A3L A2L A1L A0L INTL BUSYL GND M/S BUSYR INTR A0R A1R A2R A3R A4R NC NC C144-4 Pin Definitions Left Port I/O0L−7L(8L) A0L−12L CEL OEL R/WL SEML Right Port I/O0R−7R(8R) A0R−12R CER OER R/WR SEMR Data bus Input/Output Address Lines Chip Enable Output Enable Read/Write Enable Semaphore Enable. When asserted LOW, allows access to eight semaphores. The three least significant bits of the address lines will determine which semaphore to write or read. The I/O0 pin is used when writing to a semaphore. Semaphores are requested by writing a 0 into the respective location. Interrupt Flag. INTL is set when right port writes location 1FFE and is cleared when left port reads location 1FFE. INTR is set when left port writes location 1FFF and is cleared when right port reads location 1FFF. Busy Flag Master or Slave Select Power Ground Description INTL INTR BUSYL M/S VCC GND BUSYR 3 CY7C145 CY7C144 Selection Guide 7C144-15 7C145-15 Maximum Access Time (ns) Maximum Operating Current (mA) Maximum Standby Current for ISB1 (mA) 15 220 60 7C144-25 7C145-25 25 180 40 7C144-35 7C145-35 35 160 30 7C144-55 7C145-55 55 160 30 Maximum Ratings (Above which the useful life may be impaired. For user guidelines, 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 +7.0V DC Voltage Applied to Outputs in High Z State .....................................................− 0.5V to +7.0V DC Input Voltage[5] ..............................................−0.5V to +7.0V Output Current into Outputs (LOW)............................. 20 mA Static Discharge Voltage .......................................... >2001V (per MIL-STD-883, Method 3015) Latch-Up Current .................................................... >200 mA Operating Range Range Commercial Industrial Ambient Temperature 0°C to +70°C −40°C to +85°C VCC 5V ± 10% 5V ± 10% Electrical Characteristics Over the Operating Range 7C144-15 7C145-15 Parameter VOH VOL VIH VIL IIX IOZ ICC ISB1 ISB2 ISB3 Description Output HIGH Voltage Output LOW Voltage Input HIGH Voltage Input LOW Voltage Input Leakage Current Output Leakage Current Operating Current Standby Current (Both Ports TTL Levels) Standby Current (One Port TTL Level) GND < VI < VCC Outputs Disabled, GND < VO < VCC VCC = Max., IOUT = 0 mA Com’l Outputs Disabled Ind CEL and CER > VIH, f = fMAX[7] CEL or CER > VIH, f = fMAX[7] Com’l Ind Com’l Ind Com’l Ind Com’l Ind 125 15 130 −10 −10 Test Conditions VCC = Min., IOH = −4.0 mA VCC = Min., IOL = 4.0 mA 2.2 0.8 +10 +10 220 60 −10 −10 Min. 2.4 0.4 2.2 0.8 +10 +10 180 190 40 50 110 120 15 30 100 115 mA mA mA mA Max. 7C144-25 7C145-25 Min. 2.4 0.4 Max. Unit V V V V µA µA mA Standby Current Both Ports (Both Ports CMOS Levels) CE and CER > VCC – 0.2V, VIN > VCC – 0.2V or VIN < 0.2V, f = 0[7] Standby Current (One Port CMOS Level) One Port CEL or CER > VCC – 0.2V, VIN > VCC – 0.2V or VIN < 0.2V, Active Port Outputs, f = fMAX[7] ISB4 Notes: 5. Pulse width < 20 ns. 6. TA i s the “instant on” case temperature. 7. fMAX = 1 /t RC = A ll inputs cycling at f = 1/t RC (except output enable). f = 0 means no address or control lines change. This applies only to inputs at CMOS level standby I SB3 . 4 CY7C145 CY7C144 Electrical Characteristics Over the Operating Range (continued) 7C144-35 7C145-35 Parameter VOH VOL VIH VIL IIX IOZ ICC ISB1 ISB2 ISB3 Description Output HIGH Voltage Output LOW Voltage Input HIGH Voltage Input LOW Voltage Input Leakage Current Output Leakage Current Operating Current Standby Current (Both Ports TTL Levels) Standby Current (One Port TTL Level) GND < VI < VCC Outputs Disabled, GND < VO < VCC VCC = Max., IOUT = 0 mA Com’l Outputs Disabled Ind CEL and CER > VIH, f = fMAX[7] CEL or CER > VIH, f = fMAX[7] Com’l Ind Com’l Ind Com’l Ind Com’l Ind −10 −10 Test Conditions VCC = Min., IOH = −4.0 mA VCC = Min., IOL = 4.0 mA 2.2 0.8 +10 +10 160 180 30 40 100 110 15 30 90 100 −10 −10 Min. 2.4 0.4 2.2 0.8 +10 +10 160 180 30 40 100 110 15 30 90 100 mA mA mA mA Max. 7C144-55 7C145-55 Min. 2.4 0.4 Max. Unit V V V V µA µA mA Standby Current Both Ports (Both Ports CMOS Levels) CE and CER > VCC – 0.2V, VIN > VCC – 0.2V or VIN < 0.2V, f = 0[7] Standby Current (One Port CMOS Level) One Port CEL or CER > VCC – 0.2V, VIN > VCC – 0.2V or VIN < 0.2V, Active Port Outputs, f = fMAX[7] ISB4 ] Capacitance[8] Parameter CIN COUT Description Input Capacitance Output Capacitance Test Conditions TA = 2 5° C, f = 1 MHz, V CC = 5 .0V Max. 10 15 Unit pF pF Note: 8. Tested initially and after any design or process changes that may affect these parameters. 5 CY7C145 CY7C144 AC Test Loads and Waveforms 5V R1=893 Ω OUTPUT C = 30 pF R2=347 Ω OUTPUT C=30pF VTH =1.4V (a) Normal Load (Load1) C144-5 5V RTH =250 Ω OUTPUT C = 5 pF R2=347Ω R1=893Ω (b) Thévenin Equivalent (Load 1) C144-6 (c) Three-State Delay (Load 3) C144-7 ALL INPUT PULSES OUTPUT C = 30 pF 3.0V GND 10% 90% 90% 10% ≤ 3 ns C144-9 ≤ 3 ns Load (Load 2) C144-8 Switching Characteristics Over the Operating Range[9] 7C144-15 7C145-15 Parameter READ CYCLE tRC tAA tOHA tACE tDOE tLZOE [10, 11,12] 7C144-25 7C145-25 Min. 25 Max. 7C144-35 7C145-35 Min. 35 Max. 7C144-55 7C145-55 Min. 55 Max. Unit ns 55 3 ns ns 55 25 3 25 3 25 0 55 ns ns ns ns ns ns ns ns Description Read Cycle Time Address to Data Valid Output Hold From Address Change CE LOW to Data Valid OE LOW to Data Valid OE Low to Low Z OE HIGH to High Z CE LOW to Low Z CE HIGH to High Z CE LOW to Power-Up CE HIGH to Power-Down Min. 15 Max. 15 3 15 10 3 10 3 10 0 15 0 3 3 3 25 3 25 15 3 15 3 15 0 25 35 35 20 20 20 35 tHZOE[10, 11,12] tLZCE[10, 11,12] tHZCE[10, 11,12] tPU[12] tPD[12] Notes: 9. 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 a nd 30-pF load capacitance. 10. At any given temperature and voltage condition for any given device, tHZCE i s less than tLZCE and tHZOE i s less than t LZOE . 11. Test conditions used are Load 3. 12. This parameter is guaranteed but not tested. 6 CY7C145 CY7C144 Switching Characteristics Over the Operating Range[9] (continued) 7C144-15 7C145-15 Parameter WRITE CYCLE tWC tSCE tAW tHA tSA tPWE tSD tHD tHZWE[11,12] tLZWE[11,12] tWDD[13] tDDD[13] Write Cycle Time CE LOW to Write End Address Set-Up to Write End Address Hold From Write End Address Set-Up to Write Start Write Pulse Width Data Set-Up to Write End Data Hold From Write End R/W L OW to High Z R/W H IGH to Low Z Write Pulse to Data Delay Write Data Valid to Read Data Valid BUSY LOW from Address Match BUSY HIGH from Address Mismatch BUSY LOW from CE LOW BUSY HIGH from CE HIGH Port Set-Up for Priority R/W L OW after BUSY L OW R/W HIGH after BUSY H IGH BUSY HIGH to Data Valid INT Set Time INT Reset Time SEM Flag Update Pulse (OE or SEM) SEM Flag Write to Read Time SEM Flag Contention Window 10 5 5 5 0 13 15 15 15 10 5 5 3 30 25 15 12 12 2 0 12 10 0 10 3 50 30 25 20 20 2 0 20 15 0 15 3 60 35 35 30 30 2 0 25 15 0 20 3 70 40 55 45 45 2 0 40 25 0 25 ns ns ns ns ns ns ns ns ns ns ns ns Description Min. Max. 7C144-25 7C145-25 Min. Max. 7C144-35 7C145-35 Min. Max. 7C144-55 7C145-55 Min. Max. Unit BUSY TIMING[14] tBLA tBHA tBLC tBHC tPS tWB tWH tBDD tINS tINR tSOP tSWRD tSPS 15 15 15 15 5 0 20 25 25 25 15 5 5 20 20 20 20 5 0 30 35 25 25 20 5 5 20 20 20 20 5 0 30 55 35 35 30 30 30 30 ns ns ns ns ns ns ns ns ns ns ns ns ns INTERRUPT TIMING[14] SEMAPHORE TIMING Notes: 13. For information on part-to-part delay through RAM cells from writing port to reading port, refer to Read Timing with Port-to-Port Delay waveform. 14. Test conditions used are Load 2. 7 CY7C145 CY7C144 Switching Waveforms Read Cycle No. 1 (Either Port Address Access)[15, 16] tRC ADDRESS tAA tOHA DATA OUT PREVIOUS DATA VALID DATA VALID C144-10 Read Cycle No. 2 (Either Port CE/OE Access)[15, 17, 18] SEM or CE OE tACE tDOE tHZOE tHZCE tLZOE tLZCE DATA OUT tPU ICC ISB DATA VALID tPD C144-11 Read Timing with Port-to-Port Delay (M/S=L)[19, 20] tWC ADDRESSR R/WR MATCH t PWE t SD t HD DATAIN R VALID ADDRESSL MATCH tDDD DATA OUTL tWDD VALID C144-12 Notes: 15. R/W i s HIGH for read cycle. 16. Device is continuously selected CE = L OW and OE = L OW. This waveform cannot be used for semaphore reads. 17. Address valid prior to or coincident with CE t ransition LOW. 18. CE L = L , SEM = H when accessing RAM. CE = H, SEM = L w hen accessing semaphores. 19. BUSY = H IGH for the writing port. 20. CE L = CE R = LOW. 8 CY7C145 CY7C144 Switching Waveforms (continued) Write Cycle No. 1: OE Three-State Data I/Os (Either Port)[21, 22, 23] tWC ADDRESS tSCE SEM OR CE tAW R/W tSA DATA IN tPWE tSD DATA VALID tHD tHA OE t HIGH IMPEDANCE C144-13 tHZOE DATA OUT LZOE Write Cycle No. 2: R/W Three-State Data I/Os (Either Port)[21, 23, 24] tWC ADDRESS tSCE SEM OR CE tSA R/W tAW tPWE tHA tSD DATA IN tHZWE DATA OUT DATA VALID tHD tLZWE HIGH IMPEDANCE C144-14 Notes: 21. The internal write time of the memory is defined by the overlap of CE o r SEM LOW and R/W LOW. Both signals must be LOW to initiate a write, and either signal can terminate a write by going HIGH. The data input set-up and hold timing should be referenced to the rising edge of the signal that terminates the write. 22. If OE i s LOW during a R/W controlled write cycle, the write pulse width must be the larger of t PWE o r (tHZWE + t SD) to allow the I/O drivers to turn off and data to be placed on the bus for the required tSD. If OE i s HIGH during a R/W controlled write cycle (as in this example), this requirement does not apply and the write pulse can be as short as the specified t PWE . 23. R/W m ust be HIGH during all address transitions. 24. Data I/O pins enter high impedance when OE i s held LOW during write. 9 CY7C145 CY7C144 Switching Waveforms (continued) Semaphore Read After Write Timing, Either Side[25] tAA A0−A 2 VALID ADDRESS tAW SEM tSCE tSD I/O0 tSA R/W tSWRD OE WRITE CYCLE tSOP READ CYCLE C144-15 tOHA VALID ADDRESS tACE tSOP tHA DATA IN VALID tPWE tHD DATA OUT VALID tDOE Semaphore Contention[26, 27, 28] A0L−A 2L MATCH R/WL SEML tSPS A0R−A 2R MATCH R/WR SEM R C144-16 Notes: 25. CE = HIGH for the duration of the above timing (both write and read cycle). 26. I/O0R = I/O0L = LOW (request semaphore); CE R = CE L = HIGH 27. Semaphores are reset (available to both ports) at cycle start. 28. If tSPS i s violated, the semaphore will definitely be obtained by one side or the other, but there is no guarantee which side will control the semaphore. 10 CY7C145 CY7C144 Switching Waveforms (continued) Read with BUSY (M/S=HIGH)[20] tWC ADDRESSR R/WR MATCH tPWE tSD DATAINR tPS ADDRESSL tBLA BUSYL tDDD DATA OUTL tWDD MATCH VALID tHD tBHA tBDD VALID C144–17 Write Timing with Busy Input (M/S=LOW) tPWE R/W tWB BUSY tWH C144–18 11 CY7C145 CY7C144 Switching Waveforms (continued) Busy Timing Diagram No. 1 (CE Arbitration)[29] CEL Valid First: ADDRESS L,R CEL tPS CER tBLC BUSYR C144-19 ADDRESS MATCH tBHC CER Valid First: ADDRESS L,R CER tPS CEL tBLC BUSYL C144-20 ADDRESS MATCH tBHC Busy Timing Diagram No. 2 (Address Arbitration)[29] Left Address Valid First: tRC or tWC ADDRESS L ADDRESS MATCH tPS ADDRESS R tBLA BUSY R C144-21 ADDRESS MISMATCH tBHA Right Address Valid First: tRC or tWC ADDRESS R ADDRESS MATCH tPS ADDRESS L tBLA BUSYL C144-22 ADDRESS MISMATCH tBHA Notes: 29. If tPS i s violated, the busy signal will be asserted on one side or the other, but there is no guarantee on which side BUSY w ill be asserted 12 CY7C145 CY7C144 Switching Waveforms (continued) Interrupt Timing Diagrams Left Side Sets INTR: ADDRESS L CE L R/W L tWC WRITE 1FFF tHA [30] INT R tINS [31] C144-23 Right Side Clears INT R: ADDRESS R CER tINR [31] R/WR OE R tRC READ 1FFF INTR C144-24 Right Side Sets INT L: tWC ADDRESS R CE R WRITE 1FFE tHA [30] R/W R INT L tINS [31] C144-25 Left Side Clears INTL: ADDRESS R CEL tINR [31] R/WL OEL INTL tRC READ 1FFE C144-26 Notes: 30. tHA d epends on which enable pin (CEL o r R/WL ) is deasserted first. 31. tINS o r tINR d epends on which enable pin (CE L or R/WL) is asserted last. 13 CY7C145 CY7C144 Architecture The CY7C144/5 consists of a an array of 8K words of 8/9 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 CY7C144/5 can function as a Master (BUSY pins are outputs) or as a slave (BUSY pins are inputs). The CY7C144/5 has 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. in master mode are push-pull outputs and do not require pull-up resistors to operate. Master/Slave An 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 of slave devices must be delayed until after the BUSY input has settled. Otherwise, the slave chip may begin a write cycle during a contention situation.When presented a HIGH input, 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 CY7C144/5 provides 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 0 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 0), it assumes control over the shared resource, otherwise (reads a 1) 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 1), the left side will succeed in gaining control of the semaphore. If the left side no longer requires the semaphore, a 1 is written to cancel its request. Semaphores are accessed by asserting SEM LOW. The SEM pin functions as a chip enable 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 0 is written to the left port of an unused semaphore, a 1 will appear at the same semaphore address on the right port. That semaphore can now only be modified by the side showing 0 (the left port in this case). If the left port now relinquishes control by writing a 1 to the semaphore, the semaphore will be set to 1 for both sides. However, if the right port had requested the semaphore (written a 0) 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 eight/nine data lines output the semaphore value. The read value is latched in an output 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. Initialization of the semaphore is not automatic and must be reset during initialization program at power-up. All Semaphores on both sides should have a one written into them at initialization from both sides to assure that they will be free when needed. 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 OE pin (see Write Cycle No.1 waveform) or the R/W p in (see Write Cycle No. 2 waveform). Data can be written to the device tHZOE a fter the OE is deasserted or tHZWE after the falling edge of R/W. Required inputs for non-contention operations are summarized in Table 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 be met before the data is read on the output; otherwise the data read is not deterministic. Data will be valid on the port tDDD a fter 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 are asserted. If the user of the CY7C144/5 wishes to access a semaphore flag, then the SEM pin must be asserted instead of the CE pin. Interrupts The interrupt flag (INT) permits communications between ports.When the left port writes to location 1FFF, the right port’s interrupt flag (INTR) is set. This flag is cleared when the right port reads that same location. Setting the left port’s interrupt flag (INTL) is accomplished when the right port writes to location 1FFE. This flag is cleared when the left port reads location 1FFE. The message at 1FFF or 1FFE is user-defined. See Table 2 for input requirements for INT. INTR and INTL are push-pull outputs and do not require pull-up resistors to operate. Busy The CY7C144/5 provides on-chip arbitration to alleviate 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 guaranteed which one. BUSY will be asserted tBLA after an address match or tBLC after CE is taken LOW. BUSYL and BUSYR 14 CY7C145 CY7C144 Table 1. Non-Contending Read/Write. Inputs CE H H X H L L L H L X R/W X H X OE X L H X L X X SEM H L X L H H L Outputs I/O0−7/8 High Z Data Out High Z Data In Data Out Data In Operation Power-Down Read Data in Semaphore I/O Lines Disabled Write to Semaphore Read Write Illegal Condition Table 2. Interrupt Operation Example (assumes BUSYL=BUSYR=HIGH). Left Port Function Set Left INT Reset Left INT Set Right INT Reset Right INT R/W X X L X CE X L L X OE X L X X A0−12 X 1FFE 1FFF X INT L H X X R/W L X X X CE L L X L Right Port OE X L X L A0−12 1FFE X X 1FFF INT X X L H Table 3. Semaphore Operation Example. Function No action Left port writes semaphore Right port writes 0 to semaphore Left port writes 1 to semaphore Left port writes 0 to semaphore Right port writes 1 to semaphore Left port writes 1 to semaphore Right port writes 0 to semaphore Right port writes 1 to semaphore Left port writes 0 to semaphore Left port writes 1 to semaphore I/O0-7/8 Left 1 0 0 1 1 0 1 1 1 0 1 I/O0-7/8 Right 1 1 1 0 0 1 1 0 1 1 1 Semaphore free Left port obtains semaphore Right side is denied access Right port is granted access to semaphore No change. Left port is denied access Left port obtains semaphore No port accessing semaphore address Right port obtains semaphore No port accessing semaphore Left port obtains semaphore No port accessing semaphore Status 15 CY7C145 CY7C144 Typical DC and AC Characteristics NORMALIZED SUPPLY CURRENT vs. SUPPLY VOLTAGE 1.4 1.2 1.0 0.8 0.6 0.6 0.4 0.2 0.0 4.0 4.5 5.0 5.5 6.0 0.4 0.2 0.6 −55 25 125 VCC =5.0V VIN =5.0V ICC ISB3 1.2 ICC 1.0 0.8 ISB3 120 80 40 0 0 1.0 2.0 3.0 4.0 5.0 AMBIENT TEMPERATURE (°C) OUTPUT VOLTAGE (V) VCC =5.0V TA =25°C 160 NORMALIZED SUPPLY CURRENT vs. AMBIENT TEMPERATURE 200 OUTPUT SOURCE CURRENT vs. OUTPUT VOLTAGE SUPPLY VOLTAGE (V) NORMALIZED ACCESS TIME vs. SUPPLY VOLTAGE 1.4 1.3 1.2 1.1 1.0 0.9 0.8 4.0 4.5 5.0 5.5 6.0 TA =25°C 1.0 1.6 1.4 NORMALIZED ACCESS TIME vs. AMBIENT TEMPERATURE 140 120 100 1.2 80 60 VCC =5.0V 0.8 0.6 −55 40 20 25 125 OUTPUT SINK CURRENT vs. OUTPUT VOLTAGE VCC =5.0V TA =25°C 1.0 2.0 3.0 4.0 5.0 0 0.0 SUPPLY VOLTAGE (V) AMBIENT TEMPERATURE (°C) OUTPUT VOLTAGE (V) TYPICAL POWER-ON CURRENT vs. SUPPLY VOLTAGE 1.00 30.0 25.0 0.75 20.0 15.0 10.0 0.25 5.0 0.0 0 1.0 2.0 3.0 4.0 5.0 0 TYPICAL ACCESS TIME CHANGE vs. OUTPUT LOADING 1.25 NORMALIZED ICC vs. CYCLE TIME VCC =5.0V TA =25°C VIN =0.5V 1.0 0.50 0.75 VCC =4.5V TA =25°C 0 200 400 600 800 1000 0.50 10 28 40 66 SUPPLY VOLTAGE (V) CAPACITANCE (pF) CYCLE FREQUENCY (MHz) 16 CY7C145 CY7C144 Ordering Information 8K x8 Dual-Port SRAM Speed (ns) 15 25 Ordering Code CY7C144-15AC CY7C144-15JC CY7C144-25AC CY7C144-25JC CY7C144-25AI CY7C144-25JI 35 CY7C144-35AC CY7C144-35JC CY7C144-35AI CY7C144-35JI 55 CY7C144-55AC CY7C144-55JC CY7C144-55AI CY7C144-55JI 8K x9 Dual-Port SRAM Speed (ns) 15 25 Ordering Code CY7C145-15AC CY7C145-15JC CY7C145-25AC CY7C145-25JC CY7C145-25AI CY7C145-25JI 35 CY7C145-35AC CY7C145-35JC CY7C145-35AI CY7C145-35JI 55 CY7C145-55AC CY7C145-55JC CY7C145-55AI CY7C145-55JI Package Name A80 J81 A80 J81 A80 J81 A80 J81 A80 J81 A80 J81 A80 J81 Package Type 80-Lead Thin Quad Flat Pack 68-Lead Plastic Leaded Chip Carrier 80-Lead Thin Quad Flat Pack 68-Lead Plastic Leaded Chip Carrier 80-Lead Thin Quad Flat Pack 68-Lead Plastic Leaded Chip Carrier 80-Lead Thin Quad Flat Pack 68-Lead Plastic Leaded Chip Carrier 80-Lead Thin Quad Flat Pack 68-Lead Plastic Leaded Chip Carrier 80-Lead Thin Quad Flat Pack 68-Lead Plastic Leaded Chip Carrier 80-Lead Thin Quad Flat Pack 68-Lead Plastic Leaded Chip Carrier Industrial Commercial Industrial Commercial Industrial Commercial Operating Range Commercial Package Name A65 J81 A65 J81 A65 J81 A65 J81 A65 J81 A65 J81 A65 J81 Package Type 64-Lead Thin Quad Flat Pack 68-Lead Plastic Leaded Chip Carrier 64-Lead Thin Quad Flat Pack 68-Lead Plastic Leaded Chip Carrier 64-Lead Thin Quad Flat Pack 68-Lead Plastic Leaded Chip Carrier 64-Lead Thin Quad Flat Pack 68-Lead Plastic Leaded Chip Carrier 64-Lead Thin Quad Flat Pack 68-Lead Plastic Leaded Chip Carrier 64-Lead Thin Quad Flat Pack 68-Lead Plastic Leaded Chip Carrier 64-Lead Thin Quad Flat Pack 68-Lead Plastic Leaded Chip Carrier Industrial Commercial Industrial Commercial Industrial Commercial Operating Range Commercial 17 CY7C145 CY7C144 Package Diagrams 64-Pin Thin Plastic Quad Flat Pack A65 80-Pin Thin Plastic Quad Flat Pack A80 18 CY7C145 CY7C144 Package Diagrams (continued) 68-Lead Plastic Leaded ChipCarrierJ81 © Cypress Semiconductor Corporation, 1996. 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