Abstract: A dynamic impedance adjustment circuit that reduces overshoot and undershoot noise while achieving fast slew rates. The dynamic impedance adjustment circuit has an output driver for selectively driving or drawing current providing source or sink current. The dynamic impedance adjustment circuit also has an a variable impedance output driver for selectively providing a dynamic current (source or sink) for a predetermined time after transitions from a logic low level to a logic high level or from a logic high level to a low logic level in the input signal. An impedance adjustment control circuit is coupled to the variable impedance output driver for automatically detecting the transitions in the input signal and for changing the impedance of the variable impedance output driver based on the input signal, enable signal, and the output node.

Abstract: Current protection circuit has a comparator having a first terminal coupled to a reference voltage, a second terminal coupled to an output node, and an output for providing a control signal based on the inputs. Current protection circuit also has a transistor having a drain electrode coupled to a first predetermined voltage, a gate electrode, and a source electrode coupled to the output node. The transistor includes a current path between the drain electrode and the source electrode for conducting an amount of current that is dependent on the voltage applied to the gate electrode. Current protection circuit also has a fold-back circuit having a first input coupled to the output node for detecting changes in the output voltage, a second input coupled to the output of comparator for receiving the control signal, and a third input for selectively changing the voltage applied to the gate electrode based the control signal and the changes in the output voltage.