12 ns PLD for legacy 5V glue logic
The Microchip ATF16V8CZ-12XC is an electrically-erasable programmable logic device (EE PLD) from the 16V8 family, offering 8 macrocells and a 12 ns propagation delay. It operates from a 5V supply rail, placing it firmly in legacy 5V logic systems — not mixed-voltage or low-power domains.
Speed and capacity — what 12 ns and 8 macrocells mean
The 12 ns propagation delay (tPD) sets the maximum combinatorial logic path this PLD can sit in without violating setup timing. For a 5V system clocked at 50 MHz (20 ns period), a 12 ns PLD leaves 8 ns for external routing and flip-flop setup — marginal but workable for simple decode or address mapping. The 8 macrocells limit the part to small-scale logic: address decoders, bus arbiters, state machines with fewer than a dozen states, or replacing a handful of 74-series TTL gates.
The 5V supply needs a 0.1 µF decoupling capacitor within 5 mm of the VCC pin; the TSSOP-20 layout is standard enough that most EDA libraries include the footprint.