324 I/O — what the pin count buys you
324 I/O in a 484-BGA. The 23x23 mm ball array requires a four-layer minimum board.
Sourcing reality — lifecycle and supply posture
The EP4CE55F23C9L has an active product status but an end-of-life hot designation.
Temperature grade — commercial only
Rated for 0°C to 85°C junction temperature.
Comparison to EP4CE75F23C7N
The EP4CE75F23C7N is the next step up in the same Cyclone IV E family: 75,408 logic elements versus 55,856, and 2,810,880 RAM bits versus 2,396,160. It drops to 292 I/O in the same 484-BGA footprint, so the board layout is pin-compatible if you leave the extra I/O balls on the smaller part unconnected. The C7N speed grade is one bin faster than the C9L, so timing closure is easier on the larger die. For a BOM that needs more fabric but the same board, the EP4CE75F23C7N is a drop-in replacement with a different configuration bitstream.
