640 logic elements and 78 I/O — glue-logic sweet spot
The LCMXO2-640HC-4TG100C packs 640 logic elements (80 LABs/CLBs, each with 8 LEs) and 78 user I/O in a 100-TQFP (14x14 mm) package. That logic density lands it between a small CPLD and a mid-range FPGA — enough for address decoding, bus bridging, or a modest state machine without the overhead of a larger fabric. The 18 Kbit embedded RAM (18432 bits) handles small FIFOs or register files; for larger buffers you would use the block RAM in the MachXO2 family's higher-density siblings.
Commercial temp grade and package fit
For extended industrial (-40°C to 100°C) or automotive use, look at the 'I' or 'U' suffix parts in the MachXO2 family — the LCMXO2-640UHC-4TG144I, for example, offers 107 I/O and a wider temperature range. The 100-TQFP (14x14 mm) with 0.5 mm pitch demands a 4-layer PCB for reliable fan-out of all 78 I/O. The supplier device package is 100-TQFP (14x14) — the same footprint as the 100-LQFP case code.