Psuedo digital ASK demodulator with integrated buck boost and USB-PD for wireless charging

Abstract

Disclosed are techniques for using a sense amplifier for the voltage path having an adjustable gain and a current amplifier for the current path having an adjustable sample-hold interval for demodulation of in-band ASK data in power transmitting devices of a wireless charging system. The sample-hold interval may be adjusted as a function of the error rate of the demodulated data and used to sample the modulated current when the adjustable gain of the voltage path is not able to track the modulated voltage. The adjustable sample-hold may function as a variable reference of a comparator used to compare the sampled current to generate the sensed current. A controller may flexibly adjust the gain, adjust the sample-hold interval, and/or select the sensed voltage or the sensed current path for further filtering, demodulation, decoding, and processing depending on the error rate under various loading, coupling scenarios, and phases of power transfer.

Dependencies are inferred from the claim text.