| Device | t(set-up) | t(hold) | t(total) |
| 74C74 | 100.0 | 0.0 | 100.0 |
| 74HC74 | 20.0 | 0.0 | 20.0 |
| 74HCT74 | 20.0 | 0.0 | 20.0 |
| 7474 | 20.0 | 5.0 | 25.0 |
| 74ALS74 | 15.0 | 10.0 | 25.0 |
| 74LS74 | 20.0 | 0.0 | 20.0 |
| 74S74 | 3.0 | 2.0 | 5.0 |
| 74LS74 | 4.5 | 0.0 | 4.5 |
| 74AC74 | 4.0 | 0.5 | 4.5 |
| 74ACT74 | 3.0 | 1.0 | 4.0 |
| 74ACTQ74 | 3.0 | 1.5 | 4.5 |
The Table above shows various Set-Up times and Hold times for a number different Logic families. The combination of the two values determine the width of the Metastability window. The larger the window, the greater the chance the device will go Metastable. In most cases newer logic families have smaller Metastability windows which reduce the chance of the device going Metastable.
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