SN74V3640-15PEU

Overview

The SN74V3640 is a 3.3-V CMOS first-in, first-out (FIFO) memory with a 1024 × 36 bit organization and a 128-pin TQFP package. It supports 166-MHz operation with a 6-ns read/write cycle time. The device features user-selectable bus sizing for input and output ports at widths of 36, 18, or 9 bits. It includes big-endian/little-endian selectable byte representation, 5-V tolerant inputs, and independent read and write clocks.

Feature Summary

• Supports flexible bus matching on both read and write ports with selectable data flow configurations.
• Provides fixed low first-word latency and zero-latency retransmit capabilities.
• Features programmable almost-empty and almost-full flags with selectable synchronous or asynchronous timing modes.
• Offers master reset to clear the entire FIFO and partial reset to retain programmable settings.

Applications

• Network buffering
• Video signal processing
• Telecommunications systems
• Data communications interfaces

Procurement Notes

Verify that the specific part number matches the required memory depth and package type. Confirm that the operating voltage range aligns with the system's power supply specifications. Ensure that the clock frequencies used in the design do not exceed the maximum rated limits defined in the datasheet.

Selection Notes

Select this component when deep memory storage and high-speed data buffering are required. Consider the SN74V3640 for applications needing flexible bus width matching between unequal data paths. Evaluate the need for independent read and write clocks to support simultaneous data operations.

Part Context

This device belongs to the SN74V36xx series of 3.3-V CMOS FIFO memories. Other members in the series include the SN74V3650 through SN74V3690, which offer varying memory depths from 2048 to 32768 words while maintaining the same 36-bit word width and interface characteristics.

Replacement Considerations

The SN74V3650, SN74V3660, SN74V3670, SN74V3680, and SN74V3690 are direct functional replacements within the same family, differing only in memory depth.

FAQ

What is the difference between standard mode and FWFT mode?

In standard mode, the first word written to an empty FIFO requires a read operation to appear on the outputs. In FWFT mode, the first word appears automatically on the outputs after three read clock transitions without requiring a read enable assertion.

How are the programmable flag offsets configured?

Offsets can be programmed using either parallel loading via the data inputs or serial loading via the serial input pin. The method is selected during the master reset cycle.