Patent ID: 7446576
Filing Date: 2008-11-04
Classification: H03K,H04L

Abstract:
1. A Signal driver circuit having a controllable slew rate, comprising: a pre-driver sub-circuit that includes a differential arrangement of gain elements and an adjustable load, wherein adjustment of the adjustable load varies an output slew rate of an output of the pre-driver sub-circuit; an output driver sub-circuit having an input coupled with the output of the pre-driver sub-circuit, wherein the output driver output sub-circuit has a slew rate controllable by varying the slew rate of the output of the pre-driver sub-circuit and a dynamic range maintainable by controlling an amplitude of the output of the pre-driver sub-circuit; and a feedback arrangement coupled to the output driver sub-circuit and to the pre-driver sub-circuit, wherein the feedback arrangement operates to control the amplitude of the pre-driver output based on an output amplitude of the output driver whereby the slew rate of the pre-driver sub-circuit is selectably settable independently of the output amplitude of the output driver.