Integrated Device Technology, Inc.

Renesas Electronics America Inc.

Nicholaus Wayne Smith

Gustavo James Mehas

Tao Qi

Amit D Bavisi

Chan Young Jeong

Jiangjian Huang

Detelin Borislavov Martchovsky

Pooja Agrawal

Damla Solmaz Acar

Rui Liu

David Wilson

Changjae Kim

Daryl Sugasawara

Ashley De Wolfe

Xinyun Gu

Aihua Lee

Tuyen Doan

Adam Matthew Bumgarner

Gabriel Aungurencei

Haiwen Jiang

Tianze Kan

Daryl Jay Sugasawara

Ashley DeWolfe

Stefan Maireanu

A method and a system may inductively determine a position of a display screen of a computing device. Associated processes may generate a magnetic field by providing an alternating current to a driver coil, and may generate a voltage at a sensor coil in response to the magnetic field. The system and method may additionally include determining a linear position of the display screen by executing an algorithm at a processor. An input to the algorithm may include voltage data associated with the voltage generated at the sensor coil. The linear position of the display screen may correspond to a size of the display screen between a minimum size and a maximum size.

Display screen position sensing using inductive sensing

A wireless transmitter coordinates changes in the transmitter's input or output voltages with changes in the transmitter's operating frequency to counteract the transmitter's output power changes while changing the voltages. When the voltages are being increased, the output frequency is moved away from the resonant frequency. Consequently, the output power increase due to the increased voltages is restrained by the frequency change. Before or after the voltage increase, increased output power can be obtained by changing the output frequency while the input and output voltages are held constant or near constant. Some embodiments follow similar procedures when reducing the transmitter's input or output voltages. Calibration is performed before power transfer to determine suitable voltage and frequency profiles for voltage change operations. Other features are also provided.

Coordinating voltage and frequency changes in wireless power transfer

A wireless power device is presented that avoids transmit conflicts. The device can include a rectifier circuit coupled to a coil; a transmit driver coupled to the rectifier circuit; a transmit detect circuit configured to detect receipt of transmitted wireless power at the coil; and a controller coupled to the transmit driver and the transmit detect circuit, the controller receiving a signal from the transmit detect circuit and providing an alert of the presence of the transmitted wireless power, the controller activating the transmit driver to transmit wireless power in absence of the signal. The wireless device can determine an operating mode and in a transmit mode determine presence of a received power. If received power is detected an alert can be provided and an off state initiated. If transmit power is not detected the transmit driver can be activated.

Wireless power Tx to Tx conflict and protection

A wireless power transmitter pulses the transmit power level unresponsively to the wireless power receiver's power requests in order to perform foreign object detection (FOD). The FOD is performed by the transmitter analyzing the receiver's responses to the pulsed power. Some embodiments avoid mistaking FOD for coil misalignment. Other features are also provided.

Foreign object detection using wireless power receiver's response to modified transmitter behavior

Methods and systems for determining a position of a structure using inductive position sensing are described. In an example, a processor may receive a plurality of data points representing a plurality of voltages. The plurality of voltages may be generated by a plurality of sensor coils based on a magnetic flux field. The magnetic flux field may be generated by a plurality of driver coils, and the plurality of voltages may vary with changes in the magnetic flux field. The processor may calibrate the plurality of data points to generate a plurality of calibrated data points. The processor may filter the plurality of calibrated data points. The processor may estimate a position of the structure based on the filtered calibrated data points, where the position of the structure may indicate a size of a size changing device.

Adaptive position detection for inductive linear position sensing

Embodiments described herein provide foreign object detection based on coil current sensing. The transmitter power loss is computed directly based on the coil current, in conjunction with, or in place of the conventional computation based on transmitter input current. The enhanced precision of the computer power loss can be used to more accurately detect a foreign object near the transmitter coil during a wireless power transfer.

Enhanced foreign object detection with coil current sensing in wireless power transfer systems

According to some embodiments, a wireless power transmitter is disclosed. The wireless power transmitter can include a plurality of transmission coils arranged to cover a charging area and coupled with a ferrite; a plurality of local power controllers, each of the plurality of local power controllers coupled to drive a subset of the plurality of transmission coils, each subset of the plurality of transmission coils including a plurality of the plurality of transmission coils; and a microcontroller unit (MCU) coupled to the plurality of local power controllers, the microcontroller unit including a MCU processor executing instructions to designate states of each of the plurality of transmission coils, the states including active, de-active, and selected for receiver detection, and executing instructions to transmit instructions to each of the plurality of local power controllers in accordance with the state designations.

Multi-coil PTX/PRX operation and control

In accordance with some embodiments of the present invention, a method of controlling and correcting negative modulation is presented. In some embodiments, a method of operating a receiver includes detecting a negative modulation and adjusting one or more parameters to force a transition to a positive modulation. The parameters can be the output voltage Vout, the transmitter input voltage Vin, or receiver structural elements.

Negative modulation solution for fixed coil designs

In accordance with embodiments of the present invention, a wireless power transmitter includes a transmit coil that includes a plurality of concentric coils; a switch circuit coupled to the plurality of concentric coils; a driver coupled to provide a voltage to the switch circuit; and a controller coupled to the switch circuit, the controller providing control signals to the switch circuit selecting to provide the voltage across one or more of the plurality of concentric coils depending on a Q-factor measuring in the presence of a receive coil. A method of operating a wireless power transmitter includes determining a measured Q-factor for each of a plurality of configurations of concentric transmit coils; determining a difference between each of the measured Q-factors and a standard Q-factor; and selecting one of the plurality of configurations based on the differences.

Q-factor determination of coil select

In accordance with some embodiments of the present invention, an ion cooling engine (ICE) controlled by a transmitting or receiving device cools a transmit or receive coil and possibly other parts of a wireless power transmitter or receiver system. In some embodiments, the ICE includes a low-voltage circuit controlled by the transmitting device and coupled to a high voltage circuit that generates the airflow. Other features are also provided.

Control of ionic cooling in wireless charging systems

A system and method of transmitting power according to some embodiments includes sequentially pinging each of a plurality of transmit coils to locate a receiver; determining one or more active coils from the plurality of transmit coils based on the location of the receiver; activating the one or more active coils in a full-bridge mode to transfer power to the receiver; determining a base efficiency based on the one or more active coils; monitoring non-active ones of the plurality of transmit coils; determining if the receiver has moved based on the monitoring; if the receiver has moved to a new position, determining secondary coils according to the new position, and transitioning power to provide power from a new active coil configuration.

Multi-coil wireless power transmitter

In accordance with some embodiments of the present invention, a wireless power receiver that ramps an ASK impedance is presented. A method of amplitude shift key (ASK) modulation in a wireless power receiver includes initiating transition of an ASK impedance from a first state to a second state, the ASK impedance being coupled to a resonant circuit that includes a wireless power receive coil that receives a time-varying magnetic field; transitioning the ASK impedance from the first state to the second state according to the transition over a plurality of switching cycles of the time-varying magnetic field; and holding the second state.

ASK modulation

Embodiments herein provide a device for calibrating a voltage driven by a PWM signal for a circuit board. The device includes a controller configured to generate the PWM signal according to a PWM duty cycle value, and a voltage regulator configured to generate an output voltage according to the PWM signal. The controller is further configured to calibrate a relationship between the PWM duty cycle value and the output voltage based on a plurality of configured PWM duty cycle values and a plurality of corresponding voltages measured from the voltage regulator, and drive the circuit board by configuring the PWM duty cycle value based on the calibrated relationship.

Fixed-frequency voltage calibration in a wireless power transfer system

Embodiments described herein provide a wireless power transmitter that dynamically adjusts the deadtime to reduce power loss. Specifically, the wireless power transmitter includes a transistor circuit for switching a first voltage at a first node and a second voltage at a second node, and a LC circuit coupled between the first node and the second node. The wireless power transmitter further includes a controller coupled to the transistor circuit. The controller is configured to determine whether either of the first voltage and the second voltage is negative during a deadtime of switching. The controller is configured to increment or decrement the deadtime by an adjustment amount depending on whether negative voltage is detected.

Growing community of inventors

La Mesa, CA, United States of America

Nicholaus Wayne Smith