摘要 |
A digital interface circuit has two inverters with different switching points, one below and one above the nominal transition point of the circuit. Each inverter controls both pull-up and pull-down output transistors. The inverter with the low switching point controls the low-to-high signal transition, while the inverter with the high switching point controls the high-to-low signal transition. Pass gates responsive through delay elements to either the circuit input, an inverter output, or the circuit output isolate the other inverter from the output transistors. The pass gates may also be tristatable by means of a logical combination of the delayed pass gate enable signals with output enable signals. In yet another embodiment, the pair of inverters are replaced by a single inverter with dual switching points.
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