Redriver to autonomously detect cable orientation

#Example embodiments disclosed herein relate to controlling the operation of a circuit.

#The integrity of signals travelling through a cable or the traces of a printed circuit board may degrade because of loss and inter-symbol interference, especially at relatively higher frequencies. A redriver may be used to solve this problem. A redriver applies equalization to compensate for channel loss and outputs signals with a high differential voltage. This may allow longer cables to be used and may promote compliance with applicable protocols and cable/connector standards.

#However, a redriver may not be able to operate effectively if certain conditions arise. One of those conditions relates to the orientation of a cable connected between a host processor (or power delivery (PD) controller) and a display, smartphone, portable hard drive, keyboard, mouse, or other device. In some cases, the host processor or PD controller may not have an opportunity to inform the redriver of the orientation of a cable in a timely manner after it is plugged in. For example, there may be a finite time window within which the host processor may accept (re)flashing of its internal memory after power on. Consequently, if (re)flashing does not occur within this time window, then a malfunction may occur. The ability to rapidly detect of the orientation of a connected cable may prevent such a malfunction.

#Additional objects and features of the invention will be more readily apparent from the following detailed description and appended claims when taken in conjunction with the drawings. Although several example embodiments are illustrated and described, like reference numerals identify like parts in each of the figures, in which:

#FIG. 1 illustrates an embodiment of system including a redriver;

#FIG. 2A illustrates an embodiment of the redriver coupled to an interface, FIG. 2B illustrates a first orientation of the interface, and FIG. 2C illustrates a second orientation of the interface;

#It should be understood that the figures are merely schematic and are not drawn to scale. It should also be understood that the same reference numerals are used throughout the figures to indicate the same or similar parts.

#The descriptions and drawings illustrate the principles of various example embodiments. It will thus be appreciated that those skilled in the art will be able to devise various arrangements that, although not explicitly described or shown herein, embody the principles of the invention and are included within its scope. Furthermore, all examples recited herein are principally intended expressly to be for pedagogical purposes to aid the reader in understanding the principles of the invention and the concepts contributed by the inventor(s) to furthering the art and are to be construed as being without limitation to such specifically recited examples and conditions. Additionally, the term, “or,” as used herein, refers to a non-exclusive or (i.e., and/or), unless otherwise indicated (e.g., “or else” or “or in the alternative”). Also, the various example embodiments described herein are not necessarily mutually exclusive, as some example embodiments can be combined with one or more other example embodiments to form new example embodiments. Descriptors such as “first,” “second,” “third,” etc., are not meant to limit the order of elements discussed, are used to distinguish one element from the next, and are generally interchangeable. Values such as maximum or minimum may be predetermined and set to different values based on the application.

#FIG. 1 illustrates an embodiment of a system 100 which includes a host system 10 coupled to a device 30 by an interface 20. The host system 10 includes a port 12, a redriver 14, and a controller 16. The port may be a type compatible with a connector on at least one end of the interface 20. The redriver 14 may perform various operations including applying equalization to compensate channel loss for purposes of outputting signals with a higher or predetermined differential voltage. The controller 16 may be an application processor (AP), a power delivery (PD) controller, a central processing unit, or another type of logic for managing operations in the host system.