HIGH-SPEED OUTPUT CIRCUIT WITH LOW VOLTAGE CAPABILITY

摘要

Output circuits that provide compatibility with various input and output voltage levels without sacrificing performance. A pull-up P12 on an output terminal is gated by an internal node PD, and the invention encompasses various circuits and means for placing a data input signal on this internal node PD. One embodiment includes a level shifter 100 on the data input path, while also providing an alternative path through the output circuit that bypasses the level shifter. When the input data value goes high, the alternative path quickly places an attenuated high value on the internal node. The level shifter then becomes active and raises the voltage on the internal node to the output power high level, ensuring that the output pull-up P12 is completely off.