Configurable wireless charging transmit and receive monitoring device

• US 10,348,139 B2
• Filed: 09/29/2017
• Issued: 07/09/2019
• Est. Priority Date: 09/29/2017
• Status: Active Grant

• Current Assignee: WiTricity Corporation
• Original Assignee: WiTricity Corporation
• Inventors: Piasecki, Douglas, You, Zhong
• Primary Examiner(s): Amaya, Carlos
• Application Number:
  US15/719,880
• Publication Number:
  US 20190103771A1
• Time in Patent Office: 648 Days
• CPC Class Codes: H02J 50/10 using inductive coupling
• CPC Class Codes: H02J 50/12 of the resonant type
• CPC Class Codes: H02J 50/60 responsive to the presence of foreign objects, e.g. detection of living beings
• CPC Class Codes: H02J 50/80 involving the exchange of data, concerning supply or distribution of electric power, between transmitting devices and receiving devices
• CPC Class Codes: H02J 7/00034 Charger exchanging data with an electronic device, i.e. telephone, whose internal battery is under charge
• CPC Class Codes: H03K 19/018521 of complementary type, e.g. CMOS
• CPC Class Codes: H03K 3/017 Adjustment of width or dutycycle of pulses pulse width modulation H03K7/08 ; to maintain energy constant H03K3/015
• CPC Class Codes: H04B 5/263 Multiple coils at either side
• CPC Class Codes: H04B 5/72 for local intradevice communication
• CPC Class Codes: H04B 5/79 for data transfer in combination with power transfer
• CPC Class Codes: H04L 25/4902 Pulse width modulation; Pulse position modulation

Abstract

A configurable transmit/receive multiplexed coil monitoring (CMCM) device is provided having a plurality of dual function I/O connections connectable to a plurality of coils. The CMCM device is configurable to selectively drive AC transmit signals to any of the plurality of dual function I/O connections, while simultaneously monitoring voltage and phase information received as AC voltages at the dual function I/O connections in a multiplexed manner. The CMCM device is further configured such that while a selected I/O connection is selected to receive voltage and phase information from a particular I/O connection, no AC transmit signal can be driven to that selected particular I/O connection. Embodiments may include a multiplexer and one or more receive circuits configured to receive and digitalize received AC signals for processing by a digital signal processor. Embodiments may also include selectable Class-D drivers connected to the plurality of I/O connection, wherein each Class-D driver may be configured to receive pulse width modulation (PWM) signals from a PWM circuit for amplification and output as an AC transmit signal.

Claims

1. An integrated circuit comprising:

N shared input/output (I/O) connections, each of the N shared I/O connections being configured to connect to N respective coils, wherein N is a positive integer greater than 1;

an analog multiplexer having N mux inputs each connected to a respective one of the N shared I/O connections, the analog multiplexer configured to direct an AC input signal from a selected one of the N mux inputs to a mux output when the analog multiplexer is enabled;

a receiver circuit configured to receive the AC input signal and convert the AC input signal to a digital signal;

a digital signal processor (DSP) configured to process the digital signal in accordance with a predetermined configuration and output processed data;

a pulse width modulation (PWM) generator configured to output PWM signals in accordance with a PWM control signal;

N gate drivers connected such that each respective gate driver receives a PWM signal from the PWM generator and a respective gate driver enable signal, each gate driver being configured to transmit an AC signal relative to the PWM signal only when enabled by the respective gate driver enable signal, the AC signal being provided to the respective one of the N shared I/O connections;

a control portion configured to provide mux enable and mux select signals to the analog multiplexer and to provide respective gate driver enable signals to respective N gate drivers in accordance with the predetermined configuration, such that when the analog multiplexer is not enabled by the mux enable signal, any of the N gate drivers can be enabled by the respective gate driver enable signal, and such that when the analog multiplexer is enabled by the mux enable signal and the mux select signal designates the selected one of the N mux inputs then any of the N gate drivers can be enabled by the respective gate driver enable signal except for one of the N gate drivers that is respective to the selected one of the N mux inputs.

2. The integrated circuit of claim 1, wherein each of the N gate drivers are class D gate drivers.

3. The integrated circuit of claim 1, wherein the DSP provides a control signal in accordance with the predetermined configuration to the control portion.

4. The integrated circuit of claim 1, wherein a control signal in accordance with the predetermined configuration is provided to the control portion from an external source.

5. The integrated circuit of claim 1, wherein each of the N shared I/O connections is a differential I/O connection comprising a group of two pins of the integrated circuit.

6. The integrated circuit of claim 1, wherein each of the N mux inputs is a differential input.

7. The integrated circuit of claim 1 wherein each of the N gate drivers provide a differential output to transmit the AC signal relative to the PWM.

8. The integrated circuit of claim 1, wherein the PWM generator is configured in accordance with the PWM control signal to output a same or different PWM signal to each of the respective N gate drivers.

9. The integrated circuit of claim 1, wherein the integrated circuit is incorporated into a wireless power transfer system having an array of N coils corresponding to the N respective coils and wherein the predetermined configuration operates to perform a foreign object detection function.

10. The integrated circuit of claim 1, wherein the DSP is further configured to determine a second voltage and a second phase of each AC input signal from the selected one of the N mux inputs relative to a previously determined first voltage and a first phase of each AC input signal from the selected one of the N mux inputs.

11. The integrated circuit of claim 10, wherein each AC input signal from a selected one of the N mux inputs is a coupled signal from at least one of a non-respective N gate driver outputs.

12. A configurable transmit/receive (TX/RX) device for driving and receiving signals between at least two coils in an array of coils comprising:

N inputs and N outputs (I/Os) that share a same respective N input and N output (N I/O) connections, wherein N is a positive integer greater than 1;

an analog multiplexer having N mux inputs each connected to a respective one of the N I/O connections, the analog multiplexer further comprising M mux outputs, where M<

N, the analog multiplexer configured to direct M AC input signals from each one of M selected ones of the N mux inputs to respective M mux outputs when the analog multiplexer is enabled;

M receiver circuits each configured to receive a respective one of the selected AC input signals from respective M mux outputs and convert the respective selected AC input signal to one of M respective digital signals;

a digital signal processor circuit (DSP) configured to process each of the M respective digital signals in accordance with a predetermined DSP configuration and output processed data adapted for use by an external device;

a pulse width modulation (PWM) generator configured to output PWM signals in accordance with a PWM control signal;

N gate drivers connected such that each respective one of the N gate drivers receives a PWM signal from the PWM generator, each respective one of the N gate drivers further receives one of N respective gate driver enable signals, each gate driver being configured to transmit an AC signal relative to its received PWM signal to the respective I/O connection only when enabled by its respective one of the N gate driver enable signals;

a control portion configured to provide mux enable and mux select signals to the analog multiplexer and to provide the N respective gate driver enable signals to respective ones of the N gate drivers in accordance with the predetermined DSP configuration and such that when the analog multiplexer is not enabled by the mux enable signal any of the N gate drivers can be enabled by the N respective gate driver enable signals, and such that when the analog multiplexer is enabled by the analog mux enable signal and the mux select signal designates the M selected ones of the N mux inputs, then any of the N gate drivers can be enabled by the N respective gate driver enable signals except for M gate drivers that are respective to the M selected ones of the N mux inputs.

13. The configurable TX/RX device of claim 12, wherein each of the N gate drivers are class D gate drivers.

14. The configurable TX/RX device of claim 12, wherein the DSP provides a control signal in accordance with the predetermined DSP configuration to the control portion.

15. The configurable TX/RX device of claim 12 wherein a control signal in accordance with the predetermined DSP configuration is provided to the control portion from an external source.

16. The configurable TX/RX device of claim 12, wherein each of the N I/O connections is a differential I/O connection comprising two electrical connections.

17. The configurable TX/RX device of claim 12, wherein each of the N mux inputs are differential inputs and each of a respective N gate driver outputs are differential outputs.

18. The configurable TX/RX device of claim 12, wherein the PWM generator comprises between 1 and N PWM generator circuits in order to output 1 to N different PWM signals selectively to each one of the N gate drivers in accordance with the PWM control signal.

19. The configurable TX/RX device of claim 12, wherein the DSP predetermined configuration is one of a foreign object detection configuration and an object position determination configuration for an array of coils connected to the I/O connections.

20. The configurable TX/RX device of claim 12, wherein the DSP is further configured to determine a second voltage and phase of at least one of N AC input signals multiplexed through the N inputs of the analog multiplexer relative to a previously determined first voltage and phase of at one of the N AC input signals multiplexed through the N inputs of the analog multiplexer.