25 ns propagation delay — the timing ceiling for this EE PLD
The GAL16V8D-25QJI is a Lattice Semiconductor EE PLD from the GAL®16V8 series, offering 8 macrocells with a maximum propagation delay (tpd) of 25 ns. This delay sets the upper bound for combinatorial logic paths — any signal through the device takes at least 25 ns from input to registered output, which limits the maximum clock frequency to roughly 40 MHz in a typical synchronous design.
Lattice Semiconductor has marked the GAL16V8D-25QJI as Obsolete. The 20-PLCC (J-Lead) package (9x9 mm body) is a standard footprint for legacy PLD sockets and rework stations. The surface-mount J-Lead form factor allows hand-soldering or hot-air rework without a full reflow profile, which is common in repair depots maintaining older boards.
What the 8 macrocells and 25 ns mean for a replacement search
Eight macrocells means the device can implement roughly 8 registered or combinatorial logic equations — enough for simple glue logic, address decoding, or state machines in a 16-bit or 8-bit bus system. The 25 ns tpd is the critical parameter: any replacement must match or beat this delay to maintain timing closure in the existing PCB layout. The EE PLD programmable type indicates the configuration is stored in EEPROM cells — it retains the logic pattern when power is removed, unlike SRAM-based FPGAs that require an external configuration memory. This is a key distinction for legacy designs that rely on instant-on behavior at power-up.