| Atmel | ||||
| Chipset Number | Frequency | FOX Specs | FOX Thru Hole Packages | FOX SMD Packages |
| AT89C2051 | 12.000000 | Standard | FOX120-20, FOXS/120-20 | FOXSD/120-20, FPX120-20, FE |
| 24.000000 | Standard | FOX240F-20, FOXS/240F-20 | FOXSD/240F-20, FPX240F-20, FE240F-20 | |
| AT89C52 | 12.000000 | Standard | FOX120-20, FOXS/120-20 | FOXSD/120-20, FPX120-20, FE |
| 16.000000 | Standard | FOX160-20, FOXS/160-20 | FOXSD/160-20, FPX160-20, FE160-20 | |
| 20.000000 | Standard | FOX200-20, FOXS/200-20 | FOXSD/200-20, FPX200-20, FE200-20 | |
| 24.000000 | Standard | FOX240F-20, FOXS/240F-20 | FOXSD/240F-20, FPX240F-20, FE240F-20 | |