| Компонент | Описание | Производитель | |
| DM54LS191 | Synchronous 4-Bit Up/Down Counters with Mode Control |
National Semiconductor |
|
| DM54LS191J | Synchronous 4-Bit Up/Down Counters with Mode Control |
National Semiconductor |
|
| DM54LS191W | Synchronous 4-Bit Up/Down Counters with Mode Control |
National Semiconductor |