| Family | Power | I/O | Comments |
| 3000 | 5V | 5V | Original |
| 4000 | 5V | 5V | 3000 with added JTAG and RAM, more power pins. |
| 4000XL | 3V3 | 3V3 | 4000 with new low voltage |
| Spartan | 5V | 5V | Standard TTL voltage |
| Spartan XL | 3V3 | 3V3 | Spartan with new standard voltage |
| Spartan 2 | 2V5 | 3V3 | Spartan XL with low core voltage |
| Virtex | 2V5 | 3V3 or 2V5 | Spartan 2 with lower I/O voltage |
| Virtex E | 1V8 | 3V3 or 2V5 | Virtex with even lower core voltage for highest speed. |