| Mfr Part # | Mfr | Series | Package | Product Status | Accessory Type |
|---|---|---|---|---|---|
| 74AC11521N | Texas Instruments | * | Bulk | Active | - |
| 74F521PC | Fairchild Semiconductor | 74F | Tube | Obsolete | - |
| SN74F520DW | Texas Instruments | * | Bulk | Active | - |
| DM74ALS521WM | Fairchild Semiconductor | 74ALS | Tube | Obsolete | - |
| DM74ALS521WMX | Fairchild Semiconductor | 74ALS | Bulk | Obsolete | - |
| DM74ALS521N | Fairchild Semiconductor | 74ALS | Tube | Obsolete | - |
| IDT74FCT521TPY | IDT, Integrated Device Technology Inc | - | Bulk | Obsolete | - |
| DM74ALS520N | Fairchild Semiconductor | 74ALS | Tube | Obsolete | - |
| CD74HCT85E | Harris Corporation | 74HCT | Tube | Obsolete | - |
| SN74LS85D | onsemi | 74LS | Tube | Obsolete | - |