Patent ID: 8754677

Claim:
An apparatus, comprising: a pull-up circuit comprising first and second switching devices coupled in series between a first voltage rail and an output, wherein the first and second switching devices are configured to turn on to cause a voltage at the output to be substantially at a steady-state first rail voltage, and wherein the first and second switching devices are configured to turn off to isolate the output from the first voltage rail when the output voltage is substantially at a steady-state second rail voltage; a pull-down circuit comprising third and fourth switching devices coupled in series between the output and a second voltage rail, wherein the third and fourth switching devices are configured to turn on to cause the output voltage to be substantially at the steady-state second rail voltage, and wherein the third and fourth switching devices are configured to turn off to isolate the output from the second voltage rail when the output voltage is substantially at the steady-state first rail voltage; and a compensation circuit configured to: apply a first compensation voltage to a first node between the first and second switching devices to maintain a first voltage across the second switching device at or below a first defined threshold, the first defined threshold being substantially less than a difference between the first and second rail voltages; apply a second compensation voltage to a second node between the third and fourth switching devices to maintain a second voltage across the third switching device at or below a second defined threshold, the second defined threshold being substantially less than the difference between the first and second rail voltages; or apply the first compensation voltage to the first node between the first and second switching devices to maintain the first voltage across the second switching device at or below the first defined threshold, and apply the second compensation voltage to the second node between the third and fourth switching devices to maintain the second voltage across the third switching device at or below the second defined threshold.