Input Timing Characteristics
                                             
                                        
Input Timing Characteristics
Non-isolated Input Performance (measured at Vcc = 5 V, Rext = 1 kΩ)
| Parameter | Symbol | Non-isolated | 
|---|---|---|
| Input Low Voltage | VL | 0.85 V | 
| Input High Voltage | VH | 4.94 V | 
| Input Threshold High Voltage | VTHH | 4.54 V | 
| Input Threshold Low Voltage | VTHL | 1.26 V | 
| Cycle Rise Time | tR | 10.8 μs | 
| Cycle Fall Time | tF | 2 μs | 
| Current | 4.1 mA | 
                                             
                                        
Opto-isolated Input Performance (Vcc = varying pk-pk)
| Parameter | Symbol | Opto-isolated 5 V, 1 kΩ | Opto-isolated 3 V, 200 Ω | 
|---|---|---|---|
| Input Low Voltage | VIL | ≤ 1.96 V | ≤ 2 V | 
| Input High Voltage | VIH | ≥ 2 V | ≥ 2.05 V | 
| Propagation Delay Low to High | tPDLH | 20.9 μs | 19.7 μs | 
| Propagation Delay High to Low | tPDHL | 5.6 μs | 16.7 μs | 
| Typical Positive Pulse Width | tMPPW | 12 μs | 12 μs | 
| Typical Negative Pulse Width | tMNPW | 6 μs | 6 μs | 
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