公开(公告)号：US11658518B2

公开(公告)日：2023-05-23

申请号：US17408824

申请日：2021-08-23

Applicant: STMicroelectronics Asia Pacific Pte Ltd

Inventor： Baranidharan Karuppusamy ,  Thet Mon Sann ,  Kien Beng Tan ,  Supriya Raveendra Hegde ,  Huiqiao He ,  Teerasak Lee

IPC: H02J50/60 ,  H02J50/12

CPC classification number: H02J50/60 ,  H02J50/12

Abstract: A wireless power circuit operable in transceiver mode and in Q-factor measurement mode includes a bridge rectifier having first and second inputs coupled to first and second terminals of a coil, and an output coupled to a rectified node. An excitation circuit coupled to the first terminal, in Q-factor measurement mode, drives the coil with a pulsed signal. A protection circuit couples the first terminal to a first node when in Q-factor measurement mode and decouples the first terminal when in transceiver mode. A controller causes the bridge rectifier to short the first and second terminals to ground during Q-factor measurement mode. A sensing circuit amplifies voltage at the first node to produce an output voltage, and in response to the voltage at the first node rising to cross a rising threshold voltage, digitizes the output voltage. The digitized output voltage is used in calculating a Q-factor of the coil.

公开(公告)号：US11152822B1

公开(公告)日：2021-10-19

申请号：US17037982

申请日：2020-09-30

Applicant: STMicroelectronics Asia Pacific Pte Ltd

Inventor： Baranidharan Karuppusamy ,  Thet Mon Sann ,  Kien Beng Tan ,  Supriya Raveendra Hegde ,  Huiqiao He ,  Teerasak Lee

IPC: H02J50/60 ,  H02J50/12

Abstract: A wireless-power-circuit is operable in transceiver-mode and Q-factor-measurement-mode, and includes a bridge coupled to a coil, and having an output coupled to a rectified-voltage node. An excitation circuit, when in Q-factor-measurement-mode, drives the coil with a pulsed signal. A protection circuit couples the coil to a first node when in Q-factor-measurement-mode and decouples the coil from the first node when in transceiver-mode. A Q-factor sensing circuit includes an amplifier having inputs coupled to the first node and a common mode voltage (Vcm), and generating an output signal having an output voltage. A comparator generates a comparison output indicating Vcm crossing of a voltage at the first terminal of the coil, a processing circuit generating an enable signal based upon the comparison output, and an analog-to-digital-converter, when enabled, digitizing the output voltage for use in calculating a Q-factor of the coil.