Synchronous FIFO for moderate-depth buffering
The Texas Instruments SN74V245-7PAG is a synchronous FIFO memory from the 74V series, organized as 4K x 18 bits (72K total). It clocks at 133 MHz with a 5 ns access time, making it suitable for rate-matching or temporary storage in data acquisition, telecom line cards, and industrial control backplanes where the bus runs at moderate speed and the data word includes a parity or control bit alongside 16 data bits.
133 MHz clock and 5 ns access — what they mean for bus timing
The 133 MHz maximum clock rate sets the synchronous interface speed for read and write operations. The 5 ns access time from clock edge to data valid gives the receiving logic a narrow but workable setup window at full speed. If the downstream device has a tighter hold requirement, the FWFT (First-Word Fall-Through) mode lets the first word appear on the outputs without a read cycle, cutting one clock of latency on the initial read.
Feature set: programmable flags, depth/width expansion
Programmable almost-full and almost-empty flags let the designer set watermark thresholds in software or via pin strapping, reducing host interrupt overhead. Expansion in depth or width is supported by cascading multiple devices — useful when the 4K x 18 native size is insufficient. Note that retransmit capability is not provided, so the FIFO cannot replay stored data without a full reset and re-fill.
Supply and temperature range
Operates from a 3 V to 3.6 V supply, typical for 3.3 V logic families. Maximum supply current is 35 mA. The 0°C to 70°C commercial temperature range limits use to indoor, temperature-controlled environments — not rated for industrial or automotive extended-temperature applications.
Package and footprint
Supplied in a 64-TQFP (10x10 mm) surface-mount package. The 0.5 mm pitch TQFP is a standard footprint for moderate-I/O logic devices, routable on two-layer boards with careful trace spacing.
Lifecycle and sourcing
The SN74V245-7PAG is listed as Active and ROHS3 compliant.
