Power source, charging system, and inductive receiver for mobile devices

Patent metadata

Field	Value
Publication number	US-11329511-B2
Application number	US-202117472351-A
Country	US
Kind code	B2
Filing date	Sep 10, 2021
Priority date	Jun 1, 2006
Publication date	May 10, 2022
Grant date	May 10, 2022

Abstract

Systems include a coil, a drive circuit, a sense circuit, and a communication and control circuit for providing power inductively to a portable device comprising a battery and an inductive receiver unit including a receiver coil and a receiver circuit. A portable device includes a battery and a receiver unit capable of receiving inductive power from a compatible inductive charging system including a base unit with a primary coil and associated circuit.

First claim

What is claimed is:

1. A system for providing power inductively to a portable device comprising a battery and an inductive receiver unit including a receiver coil and a receiver circuit, the system comprising:
a first primary coil that is substantially planar and parallel to a surface of the system for providing power inductively to the portable device;
a first drive circuit, including a FET driver, a capacitor, and a FET switch, coupled to a DC voltage input and coupled to the primary coil, wherein the drive circuit is configured to apply an alternating electrical current to the primary coil at an operating frequency and duty cycle to generate a magnetic field in a direction substantially perpendicular to the plane of the primary coil and the surface of the system to provide power inductively to the portable device when the portable device is close enough to the primary coil to receive power inductively from the primary coil;
a first sense circuit to monitor current flow through the primary coil during operation of the drive circuit to sense current modulation in the primary coil from modulation of current in the receiver coil; and
a communication and control circuit, including a microprocessor coupled to the drive circuit and the sense circuit, configured to:
detect, through the first sense circuit, communication of information in the current modulation in the primary coil;
operate the drive circuit at an operating frequency and a duty cycle to inductively transfer sufficient power to the inductive receiver unit to activate and power the receiver circuit to enable the receiver circuit to communicate the information in the current modulation in the primary coil, wherein the communication of information includes information to enable the communication and control circuit to configure the provision of power inductively to the portable device, wherein the received communication of information includes:
information corresponding to the voltage or current induced by the primary coil at an output of the receiver circuit;
a unique identification code;
a manufacturer code;
a charge algorithm profile; and
a power requirement;

from the received communication of information, determine when the portable device is close enough to the primary coil and sufficiently aligned with the primary coil for the system to inductively transfer the power from the primary coil to the receiver coil to charge the battery of the portable device;
operate the drive circuit according to the power requirement and charge algorithm profile to provide the power from the primary coil to the receiver coil to power the receiver unit and charge the battery of the portable device;
receive additional information in the current modulation in the primary coil from the modulation of the current in the receiver coil corresponding to the voltage or current at the output of the receiver circuit;
regulate in a closed loop feedback manner the voltage or current at the output of the receiver circuit in accordance with the received additional information corresponding to the voltage or current at the output of the receiver circuit by adjusting at least one of the operating frequency and the duty cycle of the drive circuit during charging of the battery of the portable device;
monitor for continued presence of the portable device and completion of the charging of the battery of the portable device based on the communication from the receiver circuit and detected by the communication and control circuit through the first sense circuit; and
if the portable device is no longer present or charging is complete, stop operation of the drive circuit for the provision of power inductively to the portable device.

2. The system of claim 1 , wherein the communication and control circuit is further configured to adjust the DC voltage input to the drive circuit.

3. The system of claim 1 further comprising:
a second primary coil;
a second drive circuit, coupled to the second primary coil;
a second sense circuit, coupled to the second primary coil; and
wherein the communication and control circuit is coupled to the second drive circuit and the second sense circuit and is configured to provide power inductively to the portable device and one or more additional portable devices simultaneously.

4. The system of claim 1 wherein the system includes at least a second primary coil and further wherein the system is configured to separately drive each of the primary coils, and, depending on the communication received from the receiver unit, select and drive a subset of the primary coils to provide power inductively to the portable device.

5. The system of claim 1 wherein the system is configured to select a subset of the primary coils based on comparison of voltage or current information received from the receiver unit through each of the primary coils.

6. The system of claim 1 wherein the system is configured to select a subset of primary coils based on a power requirement of the receiver unit.

7. The system of claim 1 wherein the system is configured to select a subset of primary coils based on compatibility of the system with the portable device.

8. The system of claim 1 wherein the system includes multiple primary coils of different sizes which the system is configured to drive separately to provide different power levels to the portable device and additional portable devices in accordance with power requirements of each of the portable devices.

9. The system of claim 1 further including a magnet at a center of the primary coil wherein the magnet is magnetized in a direction perpendicular to the surface of the system for inductively powering and charging the portable device to assist in alignment for inductive power transfer.

10. The system of claim 1 wherein the system is included as part of a mobile phone.

11. The system of claim 1 , further wherein the communication and control circuit is configured to operate the drive circuit for a short period of time to detect a current draw through the primary coil indicating a possible presence of the portable device for charging, wherein the short period of time is less than that needed to activate and power a receiver unit in a compatible portable device.

12. The system of claim 1 , wherein the communication of information generated by the receiver circuit and the additional information is encrypted for security, and the communication and control circuit is configured to process the encrypted information and the additional information.

13. The system of claim 1 , wherein the primary coil comprises a flexible Printed Circuit Board (PCB) coil with multiple layers of conductors of coil patterns electrically connected with vias between the layers.

14. The system of claim 13 , wherein the multiple layers of conductors of coil patterns have a substantially similar coil pattern.

15. The system of claim 14 , wherein each of the coil patterns includes 1 to 4 ounce (oz) copper thickness.

16. The system of claim 1 wherein the communication and control circuit is further configured to indicate visually and audibly that charging of the battery by inductive power transfer is occurring and to visually display a degree of battery charge.

17. The system of claim 13 , wherein the PCB is flexible and includes a near field communication (NFC) antenna.

18. The system of claim 1 , wherein the system is built into a laptop computer to provide an inductive charging section.

19. The system of claim 1 , wherein the system further comprises a section to inductively

Assignees

• Mojo Mobility Inc

Inventors

• Partovi Afshin
• Sears Michael

Classifications

• H02J7/90

  Regulation of charging or discharging current or voltage · CPC title

• H02J7/50

  acting upon multiple batteries simultaneously or sequentially · CPC title

• H02J50/90

  involving detection or optimisation of position, e.g. alignment · CPC title

• H02J50/402

  the two or more transmitting or the two or more receiving devices being integrated in the same unit, e.g. power mats with several coils or antennas with several sub-antennas · CPC title

• H02J7/68

  using circuits for correcting or protecting against reverse-polarity · CPC title