DESCRIPTION

The IDT723656/723666/723676 is a monolithic, high-speed, low-power, CMOS Triple Bus synchronous (clocked) FIFO memory which supports clock frequencies up to 83 MHz and has read access times as fast as 8ns. Two independent 2,048/4,096/8,192 x 36 dual-port SRAM FIFOs on board each chip buffer data between a bidirectional 36-bit bus (Port A) and two unidirectional 18-bit buses (Port B transmits data, Port C receives data.) FIFO data can be read out of Port B and written into Port C using either 18-bit or 9-bit formats with a choice of Big- or Little-Endian configurations.

FEATURES

• Memory storage capacity:

IDT723656 – 2,048 x 36 x 2

IDT723666 – 4,096 x 36 x 2

IDT723676 – 8,192 x 36 x 2

• Clock frequencies up to 83 MHz (8ns access time)

• Two independent FIFOs buffer data between one bidirectional 36-bit port and two unidirectional 18-bit ports (Port C receives and Port B transmits)

• 18-bit (word) and 9-bit (byte) bus sizing of 18 bits (word) on Ports B and C

• Select IDT Standard timing (using EFA , EFB , FFA , and FFC flag functions) or First Word Fall Through Timing (using ORA, ORB, IRA, and IRC flag functions)

• Programmable Almost-Empty and Almost-Full flags; each has five default offsets (8, 16, 64, 256 and 1024)

• Serial or parallel programming of partial flags

• Big- or Little-Endian format for word and byte bus sizes

• Loopback mode on Port A

• Retransmit Capability

• Master Reset clears data and configures FIFO, Partial Reset clears data but retains configuration settings

• Mailbox bypass registers for each FIFO

• Free-running CLKA, CLKB and CLKC may be asynchronous or coincident (simultaneous reading and writing of data on a single clock edge is permitted)

• Auto power down minimizes power dissipation

• Available in a space-saving 128-pin Thin Quad Flatpack (TQFP)

• Pin compatible to the lower density parts, IDT723626/3636/3646

• Industrial temperature range (–40°C to +85°C) is available