Output driver having improved electromagnetic compatibility (EMC) and associated methods

摘要

An integrated circuit includes an output driver circuit having a plurality of output driver devices connected in a parallel arrangement and an output driver controller that is capable of individually controlling the conducting states of the output driver devices. In at least one embodiment, the controller is capable of achieving any of a plurality of different fall times (and/or rise times) in an output signal by appropriately controlling the conducting states of the output devices if a change in the state of the output signal is desired, in some implementations, the controller is capable of achieving different waveshapes during rising and/or failing edges of an output signal.

主权项

1. An integrated circuit comprising:
an output driver circuit to generate an output signal for the integrated circuit, the output driver circuit comprising multiple driver devices connected in parallel, each of the multiple driver devices having a gate terminal, a drain terminal, and a source terminal, wherein the drain terminals of the multiple driver devices are coupled to a first node and the source terminals of the multiple driver devices are coupled to a second node; and a controller to provide individual control signals to gate terminals of the multiple driver devices to control a state of the output signal, the controller having a change state input to receive an indication to change the state of the output signal and one or more select inputs responsive to a code word indicating a manner in which the multiple driver devices are to change conducting state when the state of the output signal is being changed; wherein the controller is configured to change the conducting state of the multiple driver devices in sequence according to a first clock frequency in response to a first predetermined code word being present at the one or more select inputs and the controller is configured to change the conducting state of the multiple driver devices in sequence according to a second clock frequency in response to a second predetermined code word being present at the one or more select inputs, wherein the second predetermined code word is different from the first predetermined code word and the second clock frequency is different from the first clock frequency.