Fast wake-up of differential receivers using common mode decoupling capacitors

摘要

Embodiments of an AC coupled bus charging system are disclosed that may allow for different charging currents. The charging system may include a charging circuit and a control circuit. The charging circuit may be operable to controllably select different charging currents dependent upon the output of the control circuit.

主权项

1. An apparatus, comprising:
a capacitively coupled input/output port of an integrated circuit; a control circuit configured to:
detect a power up condition;generate a current control signal dependent upon the detected power up condition; anddetect a threshold voltage level on the capacitively coupled input/output port of the integrated circuit; and a charging circuit configured to:
source a rapid charge current or a trickle charge current to the input/output port dependent upon the current control signal; andsource a trickle current to the capacitively coupled input/output port dependent upon the detected threshold voltage level.