SN74LS668D и другие
| Компонент | Описание | Производитель | |
| SN74LS668 | SYNCHRONOUS 4-BIT UP/DOWN COUNTERS |
Texas Instruments |
 |
| SN74LS668D | SYNCHRONOUS 4-BIT UP/DOWN COUNTERS |
Texas Instruments |
|
| SN74LS668N | SYNCHRONOUS 4-BIT UP/DOWN COUNTERS |
Texas Instruments |
|