8 macrocells, 20 ns propagation delay — the legacy glue-logic workhorse
The Lattice Semiconductor GAL16V8D-20QPI is an electrically erasable PLD from the GAL®16V8 series, packing 8 macrocells in a 20-pin DIP package. It is a through-hole device (20-DIP, 0.300" body width) supplied in tube format, designed to replace multiple 20-pin PAL devices with a single reprogrammable part.
Obsolete — last-time-buy and replacement path
Lattice Semiconductor has marked the GAL16V8D-20QPI as Obsolete. A board-level redesign to a current CPLD or FPGA family is the long-term migration path.
What the 8 macrocells mean for your logic design
Eight macrocells give the GAL16V8D-20QPI the capacity to implement a handful of registered or combinatorial logic functions — think address decoding, state machines with a few states, or bus-interface glue. Each macrocell can be configured as registered (D-type flip-flop) or combinatorial, with programmable output polarity. The -20 speed grade indicates a 20 ns maximum propagation delay (tpd), which sets the ceiling for system clock rates: at 20 ns, the part can handle clock frequencies up to roughly 50 MHz in a typical registered path.
Package and board-fit: 20-pin DIP
The 20-DIP (0.300", 7.62mm) through-hole package is a standard 0.100-inch pitch dual-inline footprint. The supplier device package is 20-PDIP.