| 摘要 |
A variable voltage driver circuit produces an output swing off of a single voltage power supply which is logically configurable to allow interconnection of CMOS chips of varying technologies and power supplies. First a voltage requirement for a destination chip is identified to which a driver chip is to be coupled, and the voltage requirement for the driver chip is identified. The variable voltage driver circuit is activated to produce a variable voltage output swing off of a single voltage power supply meeting the voltage requirements of the driver chip. The driver has data input, and level selection inputs and pins which select and enable the driver independent of the output level state that the driver is in. The driver has predriver stage having a data input and a first and a second driver output level input for determining the voltage level at the output, and having control circuits for setting output states at the output stage to a supply level, intermediate voltage level, and a disabled level, and an output stage, having devices which establish a down level to set a logical state, and an up level and an intermediate level for setting a different logical state. A logical state level at the input will normally result in an output at the same logical state level but selection of driver output level inputs determines the voltage level at the output for one of the logical state levels, so that a selected one of said driver output level inputs determines the actual output voltage of the circuit.
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