View IDT7280_74385.PDF datasheet online --- IC-ON-LINE

Datasheet File OCR Text:

CMOS DUAL ASYNCHRONOUS FIFO DUAL 256 x 9, DUAL 512 x 9, DUAL 1,024 x 9, DUAL 2,048 x 9, DUAL 4,096 x 9, DUAL 8,192 x 9
IDT7280 IDT7281 IDT7282 IDT7283 IDT7284 IDT7285
FEATURES:
* * * * * * *
DESCRIPTION:
The IDT7280/7281/7282/7283/7284/7285 are dual-FIFO memories that load and empty data on a first-in/first-out basis. These devices are functional and compatible to two IDT7200/7201/7202/7203/7204/7205 FIFOs in a single package with all associated control, data, and flag lines assigned to separate pins. The devices use Full and Empty flags to prevent data overflow and underflow and expansion logic to allow for unlimited expansion capability in both word size and depth. The reads and writes are internally sequential through the use of ring pointers, with no address information required to load and unload data. Data is toggled in and out of the devices through the use of the Write (W) and Read (R) pins. The devices utilize a 9-bit wide data array to allow for control and parity bits at the user's option. This feature is especially useful in data communications applications where it is necessary to use a parity bit for transmission/reception error checking. It also features a Retransmit (RT) capability that allows for reset of the read pointer to its initial position when RT is pulsed LOW to allow for retransmission from the beginning of data. A Half-Full Flag is available in the single device mode and width expansion modes. These FIFOs are fabricated using IDT's high-speed CMOS technology. They are designed for those applications requiring asynchronous and simultaneous read/writes in multiprocessing and rate buffer applications.
* * * * * * * * *
The IDT7280 is equivalent to two IDT7200 256 x 9 FIFOs The IDT7281 is equivalent to two IDT7201 512 x 9 FIFOs The IDT7282 is equivalent to two IDT7202 1,024 x 9 FIFOs The IDT7283 is equivalent to two IDT7203 2,048 x 9 FIFOs The IDT7284 is equivalent to two IDT7204 4,096 x 9 FIFOs The IDT7285 is equivalent to two IDT7205 8,192 x 9 FIFOs Low power consumption -- Active: 685 mW (max.) -- Power-down: 83 mW (max.) Ultra high speed--12 ns access time Asynchronous and simultaneous read and write Offers optimal combination of data capacity, small foot print and functional flexibility Ideal for bi-directional, width expansion, depth expansion, bus-matching, and data sorting applications Status Flags: Empty, Half-Full, Full Auto-retransmit capability High-performance CMOS technology Space-saving TSSOP Industrial temperature range (-40C to +85C) is available
FUNCTIONAL BLOCK DIAGRAM
DATA INPUTS (DA0-DA8) WA WRITE CONTROL WRITE POINTER THREESTATE BUFFERS RAM ARRAY A 256 x 9 512 x 9 1,024 x 9 2,048 x 9 4,096 x 9 8,192 x 9
RSA
WB WRITE CONTROL WRITE POINTER
DATA INPUTS (DB0-DB8) RAM ARRAY B 256 x 9 512 x 9 1,024 x 9 2,048 x 9 4,096 x 9 8,192 x 9 THREESTATE BUFFERS
RSB
READ POINTER
READ POINTER
RA
READ CONTROL FLAG LOGIC EXPANSION LOGIC
RESET LOGIC
READ CONTROL FLAG LOGIC EXPANSION LOGIC
RESET LOGIC
XIA
XOA/HFA
FFA
EFA
DATA OUTPUTS (QA0-QA8)
FLA/RTA
RB
XIB
XOB/HFB
FFB
EFB
DATA OUTPUTS (QB0-QB8)
FLB/RTB
3208 drw 01
IDT and the IDT logo are registered trademarks of Integrated Device Technology, Inc
COMMERCIAL AND INDUSTRIAL TEMPERATURE RANGES
1
2002 Integrated Device Technology, Inc. All rights reserved. Product specifications subject to change without notice.
SEPTEMBER 2002
DSC-3208/5
IDT7280/7281/7282/7283/7284/7285 5V ASYNCHRONOUS FIFO DUAL 256 x 9, 512 x 9, 1,024 x 9, 2,048 x 9, 4,096 x 9 and 8,192 x 9
COMMERCIAL TEMPERATURE RANGE
PIN CONFIGURATION
FFA QA0 QA1 QA2 QA3 QA8 GND RA QA4 QA5 QA6 QA7 XOA/HFA EFA FFB QB0 QB1 QB2 QB3 QB8 GND RB QB4 QB5 QB6 QB7 XOB/HFB EFB 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 56 55 54 53 52 51 50 49 48 47 46 45 44 43 42 41 40 39 38 37 36 35 34 33 32 31 30 29 XIA DA0 DA1 DA2 DA3 DA8 WA VCC DA4 DA5 DA6 DA7 FLA/RTA RSA XIB DB0 DB1 DB2 DB3 DB8 WB VCC DB4 DB5 DB6 DB7 FLB/RTB RSB
3208 drw 02
ABSOLUTE MAXIMUM RATINGS
Symbol VTERM TSTG IOUT Rating Terminal Voltage with Respect to GND Storage Temperature DC Output Current Com'l & Ind'l -0.5 to +7.0 -55 to +125 -50 to +50 Unit V C mA
NOTE: 1. Stresses greater than those listed under ABSOLUTE MAXIMUM RATINGS may cause permanent damage to the device. This is a stress rating only and functional operation of the device at these or any other conditions above those indicated in the operational sections of this specification is not implied. Exposure to absolute maximum rating conditions for extended periods may affect reliability.
RECOMMENDED DC OPERATING CONDITIONS
Symbol VCC GND VIH(1) VIL(2) TA TA Parameter Supply Voltage Supply Voltage Input High Voltage Input Low Voltage Operating Temperature Commercial Operating Temperature Industrial Min. 4.5 0 2.0 -- 0 -40 Typ. 5.0 0 -- -- -- -- Max. 5.5 0 -- 0.8 70 85 Unit V V V V C C
TSSOP (SO56-2, order code: PA) TOP VIEW
NOTES: 1. For RT/RS/XI input, VIH = 2.6V (commercial). 2. 1.5V undershoots are allowed for 10ns once per cycle.
DC ELECTRICAL CHARACTERISTICS
(Commercial: VCC = 5V 10%, TA = 0C to +70C; Industrial: VCC = 5V 10%, TA = -40C to +85C)
IDT7280L IDT7281L IDT7282L Commercial & Industrial(1) tA = 12, 15 ns Min. Max. -1 1 -10 10 2.4 -- -- 0.4 -- 125(6) -- 15 IDT7283L IDT7284L IDT7285lL Commercial & Industrial(1) tA = 12, 15 ns Min. Max. -1 -- -10 10 2.4 -- -- 0.4 -- 150 -- 15
Symbol ILI(2) ILO(3) VOH VOL ICC1(4,5) ICC2(4,7)
Parameter Input Leakage Current (Any Input) Output Leakage Current Output Logic "1" Voltage IOH = -2mA Output Logic "0" Voltage IOL = 8mA Active Power Supply Current (both FIFOs) Standby Current (R=W=RS=FL/RT=VIH)
Unit A A V V mA mA
NOTES: 1. Industrial temperature range product for the 15ns speed grade is available as a standard device. 2. Measurements with 0.4 VIN VCC. 3. R VIH, 0.4 VOUT VCC. 4. Tested with outputs open (IOUT = 0). 5. Tested at f = 20 MHz. 6. Typical ICC1 = 2*[15 + 2*fS + 0.02*CL*fS] (in mA) with VCC = 5V, TA = 25oC, fS = WCLK frequency = RCLK frequency (in MHz, using TTL levels), data switching at fS/2, CL = capacitive load (in pF). 7. All Inputs = VCC - 0.2V or GND + 0.2V.
AC TEST CONDITIONS
Input Pulse Levels Input Rise/Fall Times Input Timing Reference Levels Output Reference Levels Output Load
5V TO OUTPUT PIN 1.1K 30pF*
3208 drw 03 or equivalent circuit
GND to 3.0V 5ns 1.5V 1.5V See Figure 1
CAPACITANCE (TA = +25oC, f = 1.0 MHz)
Symbol CIN COUT Parameter Input Capacitance Output Capacitance Condition VIN = 0V VOUT = 0V Max. 8 8 Unit pF pF
680
NOTE: 1. Characterized values, not currently tested.
Figure 1. Output Load
* Includes scope and jig capacitances.
2
IDT7280/7281/7282/7283/7284/7285 5V ASYNCHRONOUS FIFO DUAL 256 x 9, 512 x 9, 1,024 x 9, 2,048 x 9, 4,096 x 9 and 8,192 x 9
COMMERCIAL TEMPERATURE RANGE
AC ELECTRICAL CHARACTERISTICS(1)
(Commercial: VCC = 5V 10%, TA = 0C to +70C; Industrial: VCC = 5V 10%, TA = -40C to +85C)
Commercial IDT7280L12 IDT7281L12 IDT7282L12 IDT7283L12 IDT7284L12 IDT7285L12 Min. Max. -- 20 -- 8 12 3 5 5
(4) (4,5)
Symbol tS tRC tA tRR tRPW tRLZ tWLZ tDV tRHZ tWC tWPW tWR tDS tDH tRSC tRS tRSS tRSR tRTC tRT tRTS tRTR tEFL tHFH,FFH tRTF tREF tRFF tRPE tWEF tWFF tWHF tRHF tWPF tXOL tXOH tXI tXIR tXIS Shift Frequency Read Cycle Time Access Time
Parameter
Commercial & Industrial(2) IDT7280L15 IDT7281L15 IDT7282L15 IDT7283L15 IDT7284L15 IDT7285L15 Min. Max. -- 25 -- 10 15 3 5 5 -- 25 15 10 11 0 25 15 15 10 25 15 15 10 -- -- -- -- -- 15 -- -- -- -- 15 -- -- 15 10 10 40 -- 15 -- -- -- -- -- 15 -- -- -- -- -- -- -- -- -- -- -- -- -- 25 25 25 15 15 -- 15 15 25 25 -- 15 15 -- -- --
Unit MHz ns ns ns ns ns ns ns ns ns ns ns ns ns ns ns ns ns ns ns ns ns ns ns ns ns ns ns ns ns ns ns ns ns ns ns ns ns
50 -- 12 -- -- -- -- -- 12 -- -- -- -- -- -- -- -- -- -- -- -- -- 12 17 20 12 14 -- 12 14 17 17 -- 12 12 -- -- --
Read Recovery Time Read Pulse Width(3) Read Pulse Low to Data Bus at Low Z(4) Write Pulse High to Data Bus at Low Z Data Valid from Read Pulse High Read Pulse High to Data Bus at High Z Write Cycle Time Write Pulse Width(3) Write Recovery Time Data Set-up Time Data Hold Time Reset Cycle Time Reset Pulse Width(3) Reset Set-up Time(4) Reset Recovery Time Retransmit Cycle Time Retransmit Pulse Width(3) Retransmit Set-up Time(4) Retransmit Recovery Time Reset to Empty Flag Low Reset to Half-Full and Full Flag High Retransmit Low to Flags Valid Read Low to Empty Flag Low Read High to Full Flag High Read Pulse Width after EF High Write High to Empty Flag High Write Low to Full Flag Low Write Low to Half-Full Flag Low Read High to Half-Full Flag High Write Pulse Width after FF High Read/Write to XO Low Read/Write to XO High XI Pulse Width(3) XI Recovery Time XI Set-up Time
-- 20 12 8 9 0 20 12 12 8 20 12 12 8 -- -- -- -- -- 12 -- -- -- -- 12 -- -- 12 8 8
NOTES: 1. Timings referenced as in AC Test Conditions. 2. Industrial temperature range product for the 15ns speed grade is available as a standard device. 3. Pulse widths less than minimum value are not allowed. 4. Values guaranteed by design, not currently tested. 5. Only applies to read data flow-through mode.
3
IDT7280/7281/7282/7283/7284/7285 5V ASYNCHRONOUS FIFO DUAL 256 x 9, 512 x 9, 1,024 x 9, 2,048 x 9, 4,096 x 9 and 8,192 x 9
COMMERCIAL TEMPERATURE RANGE
SIGNAL DESCRIPTIONS INPUTS:
DATA IN (D0 - D8) Data inputs for 9-bit wide data.
CONTROLS:
RESET (RS) Reset is accomplished whenever the Reset (RS) input is taken to a LOW state. During reset, both internal read and write pointers are set to the first location. A reset is required after power up before a write operation can take place. Both the Read Enable (R) and Write Enable (W) inputs must be in the HIGH state during the window shown in Figure 2, (i.e., tRSS before the rising edge of RS) and should not change until tRSR after the rising edge of RS. Half-Full Flag (HF) will be reset to HIGH after Reset (RS). WRITE ENABLE (W) A write cycle is initiated on the falling edge of this input if the Full Flag (FF) is not set. Data set-up and hold times must be adhered to with respect to the rising edge of the Write Enable (W). Data is stored in the RAM array sequentially and independently of any on-going read operation. After half of the memory is filled and at the falling edge of the next write operation, the Half-Full Flag (HF) will be set to LOW and will remain set until the difference between the write pointer and read pointer is less than or equal to one half of the total memory of the device. The Half-Full Flag (HF) is then reset by the rising edge of the read operation. To prevent data overflow, the Full Flag (FF) will go LOW, inhibiting further write operations. Upon the completion of a valid read operation, the Full Flag (FF) will go HIGH after tRFF, allowing a valid write to begin. When the FIFO is full, the internal write pointer is blocked from W, so external changes in W will not affect the FIFO when it is full. READ ENABLE (R) A read cycle is initiated on the falling edge of the Read Enable (R) provided the Empty Flag (EF) is not set. The data is accessed on a First-In/First-Out basis, independent of any ongoing write operations. After Read Enable (R) goes HIGH, the Data Outputs (Q0 - Q8) will return to a high impedance condition until the next Read operation. When all data has been read from the FIFO, the Empty Flag (EF) will go LOW, allowing the "final" read cycle but inhibiting further read operations with the data outputs remaining in a high impedance state. Once a valid write operation has been accomplished, the Empty Flag (EF) will go HIGH after tWEF and a valid Read can then begin. When the FIFO is empty, the internal read pointer is blocked from R so external changes in R will not affect the FIFO when it is empty. FIRST LOAD/RETRANSMIT (FL/RT) This is a dual-purpose input. In the Depth Expansion Mode, this pin is grounded to indicate that it is the first loaded (see Operating Modes). In the Single
Device Mode, this pin acts as the retransmit input. The Single Device Mode is initiated by grounding the Expansion In (XI). These devices can be made to retransmit data when the Retransmit Enable control (RT) input is pulsed LOW. A retransmit operation will set the internal read pointer to the first location and will not affect the write pointer. Read Enable (R) and Write Enable (W) must be in the HIGH state during retransmit. This feature is useful when less than 256/512/1,024/2,048/4,096/8,192 writes are performed between resets. The retransmit feature is not compatible with the Depth Expansion Mode and will affect the Half-Full Flag (HF), depending on the relative locations of the read and write pointers. EXPANSION IN (XI) This input is a dual-purpose pin. Expansion In (XI) is grounded to indicate an operation in the single device mode. Expansion In (XI) is connected to Expansion Out (XO) of the previous device in the Depth Expansion or Daisy Chain Mode.
OUTPUTS:
FULL FLAG (FF) The Full Flag (FF) will go LOW, inhibiting further write operation, when the write pointer is one location less than the read pointer, indicating that the device is full. If the read pointer is not moved after Reset (RS), the Full-Flag (FF) will go LOW after 256 writes for IDT7280, 512 writes for the IDT7281, 1,024 writes for the IDT7282, 2,048 writes for the IDT7283, 4,096 writes for the IDT7284 and 8,192 writes for the IDT7285. EMPTY FLAG (EF) The Empty Flag (EF) will go LOW, inhibiting further read operations, when the read pointer is equal to the write pointer, indicating that the device is empty. EXPANSION OUT/HALF-FULL FLAG (XO/HF) This is a dual-purpose output. In the single device mode, when Expansion In (XI) is grounded, this output acts as an indication of a half-full memory. After half of the memory is filled and at the falling edge of the next write operation, the Half-Full Flag (HF) will be set LOW and will remain set until the difference between the write pointer and read pointer is less than or equal to one half of the total memory of the device. The Half-Full Flag (HF) is then reset by using rising edge of the read operation. In the Depth Expansion Mode, Expansion In (XI) is connected to Expansion Out (XO) of the previous device. This output acts as a signal to the next device in the Daisy Chain by providing a pulse to the next device when the previous device reaches the last location of memory. DATA OUTPUTS (Q0 - Q8) Data outputs for 9-bit wide data. This data is in a high impedance condition whenever Read (R) is in a HIGH state.
4
IDT7280/7281/7282/7283/7284/7285 5V ASYNCHRONOUS FIFO DUAL 256 x 9, 512 x 9, 1,024 x 9, 2,048 x 9, 4,096 x 9 and 8,192 x 9
COMMERCIAL TEMPERATURE RANGE
tRSC tRS RS tRSS W tRSS R tEFL EF tHFH , tFFH HF, FF
NOTES: 1. EF, FF, HF may change status during Reset, but flags will be valid at tRSC. 2. W and R = VIH around the rising edge of RS.
3208 drw 04
tRSR
Figure 2. Reset
t RC tA R t RLZ Q0-Q8 t WPW W t DS D0-D8
tRR
t RPW tA t RHZ DATA OUT VALID
t DV DATA OUT VALID t WC t WR
t DH DATA IN VALID
3208 drw 05
DATA IN VALID
Figure 3. Asynchronous Write and Read Operation
LAST WRITE R
IGNORED WRITE
FIRST READ
ADDITIONAL READS
FIRST WRITE
W tWFF FF tRFF
3208 drw 06
Figure 4. Full Flag From Last Write to First Read
5
IDT7280/7281/7282/7283/7284/7285 5V ASYNCHRONOUS FIFO DUAL 256 x 9, 512 x 9, 1,024 x 9, 2,048 x 9, 4,096 x 9 and 8,192 x 9
LAST READ W IGNORED READ FIRST WRITE ADDITIONAL WRITES FIRST READ
COMMERCIAL TEMPERATURE RANGE
R t REF EF tA DATA OUT VALID VALID
3208 drw 07
tWEF
Figure 5. Empty Flag From Last Read to First Write
tRTC tRT RT tRTS W,R t RTF HF, EF, FF FLAG VALID
3208 drw 08
tRTR
Figure 6. Retransmit
W
tWEF
EF tRPE R
3208 drw 09
Figure 7. Minimum Timing for an Empty Flag Coincident Read Pulse
R tRFF FF tWPF W
3208 drw 10
Figure 8. Minimum Timing for a Full Flag Coincident Write Pulse
6
IDT7280/7281/7282/7283/7284/7285 5V ASYNCHRONOUS FIFO DUAL 256 x 9, 512 x 9, 1,024 x 9, 2,048 x 9, 4,096 x 9 and 8,192 x 9
COMMERCIAL TEMPERATURE RANGE
W
tRHF
R tWHF HF
HALF-FULL OR LESS MORE THAN HALF-FULL HALF-FULL OR LESS
3208 drw 11
Figure 9. Half-Full Flag Timing
WRITE TO LAST PHYSICAL LOCATION
W R tXOL XO tXOH
READ FROM LAST PHYSICAL LOCATION
tXOL
tXOH
3208 drw 12
Figure 10. Expansion Out
tXI XI tXIS W R
WRITE TO FIRST PHYSICAL LOCATION
tXIR
tXIS
READ FROM FIRST PHYSICAL LOCATION
3208 drw 13
Figure 11. Expansion In
OPERATING MODES:
Care must be taken to assure that the appropriate flag is monitored by each system (i.e. FF is monitored on the device where Wis used; EF is monitored on the device where R is used). SINGLE DEVICE MODE A single IDT7280/7281/7282/7283/7284/7285 may be used when the application requirements are for 256/512/1,024/2,048/4,096/8,192 words or less. These FIFOs are in a Single Device Configuration when the Expansion In (XI) control input is grounded (see Figure 12). DEPTH EXPANSION These devices can easily be adapted to applications when the requirements are for greater than 256/512/1,024/2,048/4,096/8,192 words. Figure
14 demonstrates a four-FIFO Depth Expansion using two IDT7280/7281/ 7282/7283/7284/7285s. Any depth can be attained by adding additional IDT7280/7281/7282/7283/7284/7285s. These FIFOs operate in the Depth Expansion mode when the following conditions are met: 1. The first FIFO must be designated by grounding the First Load (FL) control input. 2. All other FIFOs must have FL in the HIGH state. 3. The Expansion Out (XO) pin of each device must be tied to the Expansion In (XI) pin of the next device. See Figure 14. 4. External logic is needed to generate a composite Full Flag (FF) and Empty Flag (EF). This requires the ORing of all EFs and ORing of all FFs (i.e. all must be set to generate the correct composite FF or EF). See Figure 14. 5. The Retransmit (RT) function and Half-Full Flag (HF) are not available in the Depth Expansion Mode.
7
IDT7280/7281/7282/7283/7284/7285 5V ASYNCHRONOUS FIFO DUAL 256 x 9, 512 x 9, 1,024 x 9, 2,048 x 9, 4,096 x 9 and 8,192 x 9
COMMERCIAL TEMPERATURE RANGE
USAGE MODES:
WIDTH EXPANSION Word width may be increased simply by connecting the corresponding input control signals of multiple FIFOs. Status flags (EF, FF and HF) can be detected from any one FIFO. Figure 13 demonstrates an 18-bit word width by using the two FIFOs contained in the IDT7280/7281/7282/7283/7284/7285s. Any word width can be attained by adding FIFOs (Figure 13). BIDIRECTIONAL OPERATION Applications which require data buffering between two systems (each system capable of Read and Write operations) can be achieved by pairing IDT7280/7281/7282/7283/7384/7285s as shown in Figure 16. Both Depth Expansion and Width Expansion may be used in this mode. DATA FLOW-THROUGH Two types of flow-through modes are permitted, a read flow-through and write flow-through mode. For the read flow-through mode (Figure 17),
the FIFO permits a reading of a single word after writing one word of data into an empty FIFO. The data is enabled on the bus in (tWEF + tA) ns after the rising edge of W, called the first write edge, and it remains on the bus until the R line is raised from LOW-to-HIGH, after which the bus would go into a three-state mode after tRHZ ns. The EF line would have a pulse showing temporary deassertion and then would be asserted. In the write flow-through mode (Figure 18), the FIFO permits the writing of a single word of data immediately after reading one word of data from a full FIFO. The R line causes the FF to be deasserted but the W line being LOW causes it to be asserted again in anticipation of a new data word. On the rising edge of W, the new word is loaded in the FIFO. The W line must be toggled when FF is not asserted to write new data in the FIFO and to increment the write pointer. COMPOUND EXPANSION The two expansion techniques described above can be applied together in a straightforward manner to achieve large FIFO arrays (see Figure 15).
(HALF-FULL FLAG) WRITE (W) 9 DATA IN (D) FULL FLAG (FF) RESET (RS)
(HF) FIFO A or B IDT 7280 7281 7282 7283 7284 7285 READ (R) 9 DATA OUT (Q) EMPTY FLAG (EF) RETRANSMIT (RT)
EXPANSION IN (XI)
3208 drw 14
Figure 12. Block Diagram of One 256 x 9, 512 x 9, 1,024 x 9, 2,048 x 9, 4,096 x 9, 8,192 x 9 FIFO Used in Single Device Mode
9 HFA 18 DATA
IN
HFB
9 FIFO A FIFO B READ (R) EMPTY FLAG (EFB)
(D)
WRITE (W) FULL FLAG (FFA) RESET (RS) 9 7280/7281/7282/ 9 7283/7284/7285
RETRANSMIT (RT)
XIA
XIB
18 DATA
OUT (Q)
3208 drw 15
Figure 13. Block Diagram of 256 x 18, 512 x 18, 1,024 x 18, 2,048 x 18, 4,096 x 18, 8,192 x 18 FIFO Memory Used in Width Expansion Mode
8
IDT7280/7281/7282/7283/7284/7285 5V ASYNCHRONOUS FIFO DUAL 256 x 9, 512 x 9, 1,024 x 9, 2,048 x 9, 4,096 x 9 and 8,192 x 9
COMMERCIAL TEMPERATURE RANGE
TABLE 1 -- RESET AND RETRANSMIT
Single Device Configuration/Width Expansion Mode
Mode Reset Retransmit Read/Write
NOTE: 1. Pointer will increment if flag is High.
RS 0 1 1
Inputs RT X 0 1
XI 0 0 0
Read Pointer
Internal Status Write Pointer Location Zero Unchanged Increment(1)
EF 0 X X
Outputs FF 1 X X
HF 1 X X
Location Zero Location Zero Increment(1)
TABLE 2 -- RESET AND FIRST LOAD TRUTH TABLE
Depth Expansion/Compound Expansion Mode
Mode Reset First Device Reset All Other Devices Read/Write RS 0 0 1 Inputs FL 0 1 X XI (1) (1) (1) Read Pointer Location Zero Location Zero X Internal Status Write Pointer Location Zero Location Zero X Outputs EF 0 0 X FF 1 1 X
10
NOTE: 1. XI is connected to XO of previous device. See Figure 14. RS = Reset Input, FL/RT = First Load/Retransmit, EF = Empty Flag Output, FF = Full Flag Output, XI = Expansion Input, HF = Half-Full Flag Output
XOA EFA
FFA
FIFO A
FLA XIA
7280/7281/ 7282/7283/ 7284/7285 W
FFB XOB EFB
R 9 Q V CC
D
9
9
FIFO B
FLB XIB XOA
FULL 9
FFA
EFA
EMPTY
FIFO A
FLA
7280/7281/ 7282/7283/ 7284/7285
FFB
XIA
XOB EFB
9 RSA
FIFO B
FLB XIB
3208 drw 16
Figure 14. Block Diagram of 1,024 x 9, 2,048 x 9, 4,096 x 9, 8,192 x 9, 16,384 x 9, 32,768 x 9 FIFO Memory (Depth Expansion)
9
IDT7280/7281/7282/7283/7284/7285 5V ASYNCHRONOUS FIFO DUAL 256 x 9, 512 x 9, 1,024 x 9, 2,048 x 9, 4,096 x 9 and 8,192 x 9
Q0-Q8 Q0-Q8 IDT7280/7281/ 7282/7283/ 7284/7285 DEPTH EXPANSION BLOCK D0-D8 D0-DN D9-DN
NOTES: 1. For depth expansion block see section on Depth Expansion and Figure 14. 2. For Flag detection see section on Width Expansion and Figure 13.
COMMERCIAL TEMPERATURE RANGE
Q9-Q17 Q9-Q17 Q(N-8)-QN Q(N-8)-QN IDT7280/7281/ 7282/7283/ 7284/7285 DEPTH EXPANSION BLOCK D(N-8)-DN D(N-8)-DN
3208 drw 17
R, W, RS
IDT7280/7281/ 7282/7283/ 7284/7285 DEPTH EXPANSION BLOCK D9-D17 D18-DN
Figure 15. Compound FIFO Expansion
WA FFA DA0-8
FIFO A IDT 7201A
RA EFA HFA QA0-8
SIDE 1
IDT 7280 7281 7282 7283 7284 7285
SIDE 2
QB0-8 RB HFB EFB
FIFO B
DB0-8 WB FFB
3208 drw 18
Figure 16. Bidirectional FIFO Mode
10
IDT7280/7281/7282/7283/7284/7285 5V ASYNCHRONOUS FIFO DUAL 256 x 9, 512 x 9, 1,024 x 9, 2,048 x 9, 4,096 x 9 and 8,192 x 9
COMMERCIAL TEMPERATURE RANGE
DATA IN W tRPE R EF tWLZ DATA OUT
Figure 17. Read Data Flow-Through Mode
tWEF
tA
tREF DATA
OUT VALID
3208 drw 19
R W tRFF FF tWFF DATA IN tA DATA OUT DATA
OUT
tWPF
tDH
IN
DATA
VALID
tDS VALID
3208 drw 20
Figure 18. Write Data Flow-Through Mode
11
ORDERING INFORMATION
IDT XXXX Device Type X Power XXX Speed X Package X Process/ Temperature Range Blank I(1) PA
Commercial (0C to +70C) Industrial (-40C to +85C) Thin Shrink SOIC (TSSOP, SO56-2)
12 15
Commercial Only Commercial and Industrial
Access Time (tA) Speed in Nanoseconds
L 7280 7281 7282 7283 7284 7285
Low Power 256 x 9 CMOS Dual Asynchronous FIFO 512 x 9 CMOS Dual Asynchronous FIFO 1,024 x 9 CMOS Dual Asynchronous FIFO 2,048 x 9 CMOS Dual Asynchronous FIFO 4,096 x 9 CMOS Dual Asynchronous FIFO 8,192 x 9 CMOS Dual Asynchronous FIFO
3208 drw 21
NOTE: 1. Industrial temperature range product for the 15ns speed grade is available as a standard device.
DATASHEET DOCUMENT HISTORY
07/13/2001 pgs. 2, 3 and 12. CORPORATE HEADQUARTERS 2975 Stender Way Santa Clara, CA 95054 for SALES: 800-345-7015 or 408-727-6116 fax: 408-492-8674 www.idt.com
12
for Tech Support: 408-330-1753 email:FIFOhelp@idt.com

▲Up To Search▲

Price & Availability of IDT7280

	To Download IDT7280 Datasheet File
If you can't view the Datasheet, Please click here to try to view without PDF Reader .