Intel Corporation
Duty cycle control circuitry for input/output (I/O) margin control

Abstract:

An input/output (I/O) circuit provides a direct current (DC) bias between I/O stages to control duty cycle of the I/O. The I/O circuit can include one or more predriver stages and one or more output stages. The predriver stages can collectively be referred to as a predriver stage, and the output stages can collectively be referred to an output stage. The output stage for a transmitter drives the signal line. The output stage for an input buffer provides a receive signal for processing by the receiver. The I/O circuit includes a control circuit to control the DC bias between the stages to provide trim adjustment of a duty cycle for the output stage.