72V295L15PF IDT, 72V295L15PF Datasheet

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... RESET PRS LOGIC IDT, IDT logo are registered trademarks of Integrated Device Technology, Inc. The SuperSync FIFO is a trademark of Integrated Device Technology, Inc. COMMERCIAL AND INDUSTRIAL TEMPERATURE RANGES ©2008 Integrated Device Technology, Inc. All rights reserved. Product specifications subject to change without notice. ...

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... The frequencies of both the RCLK and the WCLK signals may vary from MAX frequency of the one clock input with respect to the other. There are two possible timing modes of operation with these devices: IDT Standard mode and First Word Fall Through (FWFT) mode ...

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... TM SUPERSYNC FIFO 131,072 x 18, 262,144 IDT Standard mode, the first word written to an empty FIFO will not appear on the data output lines unless a specific read operation is performed. A read operation, which consists of activating REN and enabling a rising RCLK edge, will shift the word from internal memory to the data output lines ...

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... FIFO memory is full. In the FWFT mode, the IR function is selected. IR indicates whether or not there is space available for writing to the FIFO memory. In the IDT Standard mode, the EF function is selected. EF indicates whether or O not the FIFO memory is empty. In FWFT mode, the OR function is selected. ...

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... IDT72V295/72V2105 3.3V HIGH DENSITY CMOS TM SUPERSYNC FIFO 131,072 x 18, 262,144 x 18 ABSOLUTE MAXIMUM RATINGS Symbol Rating V (2) Terminal Voltage TERM with respect to GND T Storage STG Temperature I DC Output Current OUT NOTES: 1. Stresses greater than those listed under ABSOLUTE MAXIMUM RATINGS may cause permanent damage to the device ...

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... NOTES: 1. Industrial temperature range product for the 15ns speed grade is available as a standard device. 2. All AC timings apply to both Standard IDT mode and First Word Fall Through mode. 3. Pulse widths less than minimum values are not allowed. 4. Values guaranteed by design, not currently tested. ...

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... When the FIFO is full, the Input Ready (IR) flag will go HIGH, inhibiting further write operations reads are performed after a reset, IR will go HIGH after D writes to the FIFO 131,073 writes for the IDT72V295 and 262,145 writes for the IDT72V2105, respectively. Note that the additional word in FWFT mode is due to the capacity of the memory plus output register ...

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... PROGRAMMING FLAG OFFSETS Full and Empty Flag offset values are user programmable. The IDT72V295/72V2105 has internal registers for these offsets. Default set- tings are stated in the footnotes of Table 1 and Table 2. Offset values can be programmed into the FIFO in one of two ways; serial or parallel loading method ...

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... The programming method can only be selected at Master Reset. 2. Parallel reading of the offset registers is always permitted regardless of which programming method has been selected. 3. The programming sequence applies to both IDT Standard and FWFT modes. Figure 4. Programmable Flag Offset Programming Sequence COMMERCIAL AND INDUSTRIAL TEMPERATURE RANGES ...

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... RCLK edges plus t The act of reading the offset registers employs a dedicated read offset register pointer. The contents of the offset registers can be read on the Q pins when LD is set LOW and REN is set LOW. For the IDT72V295 72V2105, data are read via Q first LOW-to-HIGH transition of RCLK ...

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... Mode), for the relevant timing diagram. COMMERCIAL AND INDUSTRIAL TEMPERATURE RANGES For either IDT Standard mode or FWFT mode, updating of the PAE, HF and PAF flags begin with the rising edge of RCLK that RT is setup. PAE is synchronized to RCLK, thus on the second rising edge of RCLK after RT is setup, the PAE flag will be updated ...

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... HF goes HIGH. Whichever mode is active at the time of Partial Reset, IDT Standard mode or First Word Fall Through, that mode will remain selected. If the IDT Standard mode is active, then FF will go HIGH and EF will go LOW. If the First Word Fall Through mode is active, then OR will go HIGH, and IR will go LOW. ...

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... IR goes HIGH, inhibiting further write operations reads are performed after a reset (either MRS or PRS), IR will go HIGH after after the valid WCLK cycle. D writes to the FIFO (D = 131,073 for the IDT72V295 and 262,145 for the IDT72V2105) See Figure 9, Write Timing (FWFT Mode), for the relevant timing information. ...

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... In IDT Standard mode reads are performed after reset (MRS), PAF will go LOW after ( words are written to the FIFO. The PAF will go LOW after (131,072-m) writes for the IDT72V295 and (262,144-m) writes for the IDT72V2105. The offset “m” is the full offset value ...

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... IDT72V295/72V2105 3.3V HIGH DENSITY CMOS TM SUPERSYNC FIFO 131,072 x 18, 262,144 x 18 MRS REN WEN t FWFT FWFT/ SEN EF/OR FF/IR PAE PAF COMMERCIAL AND INDUSTRIAL TEMPERATURE RANGES RSS t t RSS t t RSS t RSS t RSS If FWFT = HIGH HIGH t RSF If FWFT = LOW LOW ...

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... IDT72V295/72V2105 3.3V HIGH DENSITY CMOS TM SUPERSYNC FIFO 131,072 x 18, 262,144 x 18 PRS REN WEN RT SEN EF/OR FF/IR PAE PAF COMMERCIAL AND INDUSTRIAL TEMPERATURE RANGES RSS t RSS t RSS t RSS t RSF t RSF t RSF t RSF t RSF Figure 6. Partial Reset Timing 16 t RSR t RSR If FWFT = HIGH HIGH ...

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... WCLK edge and a rising RCLK edge to guarantee that EF will go HIGH (after one RCLK cycle plus SKEW1 of WCLK and the rising edge of RCLK is less than HIGH. 3. First word latency 1 SKEW1 RCLK REF Figure 8. Read Cycle, Empty Flag and First Data Word Latency Timing (IDT Standard Mode) t CLK t CLKH t CLKL ...

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... IDT72V295/72V2105 3.3V HIGH DENSITY CMOS TM SUPERSYNC FIFO 131,072 x 18, 262,144 x 18 COMMERCIAL AND INDUSTRIAL TEMPERATURE RANGES 18 ...

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... IDT72V295/72V2105 3.3V HIGH DENSITY CMOS TM SUPERSYNC FIFO 131,072 x 18, 262,144 x 18 COMMERCIAL AND INDUSTRIAL TEMPERATURE RANGES 19 ...

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... No more than may be written to the FIFO between Reset (Master or Partial) and Retransmit setup. Therefore, FF will be HIGH throughout the Retransmit setup procedure 131,072 for IDT72V295 and 262,144 for IDT72V2105. 5. There must be at least two words written to the FIFO before a Retransmit operation can be invoked. ...

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... There must be at least two words written to the FIFO before a Retransmit operation can be invoked. WCLK t ENS SEN t LDS BIT 0 SI NOTE for the IDT72V295 and for the IDT72V2105. Figure 13. Serial Loading of Programmable Flag Registers (IDT Standard and FWFT Modes ENS ...

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... PAF offset . maximum FIFO depth. In IDT Standard mode 131,072 for the IDT72V295 and 262,144 for the IDT72V2105. In FWFT mode 131,073 for the IDT72V295 and 262,145 for the IDT72V2105. is the minimum time between a rising RCLK edge and a rising WCLK edge to guarantee that PAF will go HIGH (after one WCLK cycle plus t 3 ...

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... REN NOTES: 1. For IDT Standard mode maximum FIFO depth 131,072 for the IDT72V295 and 262,144 for the IDT72V2105. 2. For FWFT mode maximum FIFO depth 131,073 for the IDT72V295 and 262,145 for the IDT72V2105. Figure 18. Half-Full Flag Timing (IDT Standard and FWFT Modes) ...

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... Use an AND gate in IDT Standard mode gate in FWFT mode not connect any output control signals directly together. 3. FIFO #1 and FIFO #2 must be the same depth, but may be different word widths. Figure 19. Block Diagram of 131,072 x 36 and 262,144 x 36 Width Expansion ...

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... The IDT72V295 can easily be adapted to applications requiring depths greater than 131,072 and 262,144 for the IDT72V2105 with an 18-bit bus width. In FWFT mode, the FIFOs can be connected in series (the data outputs of one FIFO connected to the data inputs of the next) with no external logic necessary. The resulting configuration provides a total depth equivalent to the sum of the depths associated with each single FIFO ...

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... Com Onl y Cl ock Com ' l & Ind' l Speed i n Nanos econds Com Onl ower 131,072 x 18 ⎯ 3.3V Super Sy ncF IF O 262,144 x 18 ⎯ 3.3V Super Sy ncF IF O 4668 dr w24 for Tech Support: 408-360-1753 email: FIFOhelp@idt.com ) CL K ...