Method and apparatus for analog compensation of driver output signal slew rate against device impedance variation

A system comprising:

• a peripheral device;
• and
• a chipset having an I/O driver circuit coupling the peripheral device with the chipset via a connection device, the I/O driver including:
• a signal termination device coupled to a driver output pad;
• a plurality of pull-up devices, each pull-up device coupled between a driver supply voltage and the signal termination device;
• a plurality of pull-down devices, each pull-up device coupled between a driver group and the signal termination device;
• a pull-up compensation resistive element coupled, in series, between a selected pull-down device and the signal termination device;
• and
• a pull-down compensation resistive element coupled, in series, between a selected pull-up device and the signal termination device, wherein the pull-up and pull-down compensation resistive elements provide analog compensation of a driver output signal slew rate against driver impedance variation.

An electronic system comprising:

• a printed wiring board on which a parallel bus is formed;
• and
• an integrated circuit (IC) chip package being operatively installed on the board to communicate using the parallel bus, the package having an IC chip that includes a logic function section and an I/O section as an interface between the logic function section and the bus, the I/O section having a chipset driver for communicating with a peripheral device via the parallel bus, the chipset driver including:
• a pull-up compensation resistive element coupled, in series, between a selected pull-down device and the signal termination device;
• and
• a pull-down compensation resistive element coupled, in series, between a selected pull-up device and the signal termination device, wherein the pull-up and pull-down compensation resistive elements provide analog compensation of a driver output signal slew rate against driver impedance variation.