Patent ID: 9083330
Filing Date: 2015-07-14
Classification: H03K,H04L

Abstract:
1. A driver for driving a data output signal through an output pad, comprising: a pull-down section including a plurality of first dual-mode legs coupled in parallel between an output node and ground, wherein the pull-down section is configured to receive a first calibration word having a plurality of first calibration bits corresponding to the plurality of first dual-mode legs, and wherein each first dual-mode leg includes: a first resistor having a first terminal coupled to the output node; a first data transistor coupled between a second terminal for the first resistor and ground, the first data transistor configured to conduct responsive to an assertion of a complement data signal carried on a complement data node; and a first calibration transistor coupled between the second terminal and ground, the first calibration transistor configured to conduct responsive to an assertion of both the first dual-mode leg's corresponding first calibration bit and an assertion of the complement data signal; and wherein the pull-down section further includes: a plurality of first selectable capacitors corresponding to the plurality of first calibration bits, each first selectable capacitor being configured to capacitively load the complement data node responsive to the first selectable capacitor's corresponding calibration bit being de-asserted.