Integrated Device Technology, Inc.

Renesas Electronics America Inc.

Tao Qi

Gustavo James Mehas

Rui Liu

Nicholaus Wayne Smith

Chan Young Jeong

Lijie Zhao

Amit D Bavisi

Pooja Agrawal

Zhitong Guo

Siqiang Fan

Tae Kwang Park

Jiangjian Huang

Adnan Dzebic

Daryl Sugasawara

Aihua Lee

Xinyun Gu

Damla Solmaz Acar

Changjae Kim

Mihail Jefremow

Jure Menart

Tianze Kan

Daryl Jay Sugasawara

Young Chul Ryu

Steve Jaycox

Kwangmuk Choi

Krishal Jaswantsinh Solanki

Systems, apparatuses, and methods for detecting a foreign object on a wireless power charging region are described. A circuit can detect an object inductively coupled to a wireless power transmitter. The circuit can further measure an input parameter prior to a power transfer stage, the input parameter can be one of an input current and an input power. The circuit can further compare the measured input parameter with a predetermined value. The circuit can further determine whether the object is a foreign object or the wireless power receiver based on a result of the comparison between the measured input parameter with the predetermined value.

Foreign object detection based on transmitter input parameter

In an embodiment, a semiconductor device is disclosed that includes at least one processing device and firmware including a dynamic demodulation engine. The dynamic demodulation engine, when executed by the at least one processing device, is configured to obtain a digital signal waveform, dynamically select a bit detection method based at least in part on a characteristic of the digital signal waveform, perform demodulation of the digital signal waveform using the selected bit detection method and generate decoded packets based at least in part on the demodulation.

Digital demodulation for wireless power

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 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

A method of over-current protection in a wireless power receiver operating in a high-power mode includes digitally receiving an output current signal, generating an OC INT signal if the output current signal is greater than a current limit value, and if the OC INT signal is generated, transmitting Count A number of End Power Transfer (EPT) packets. If wireless power transmission has not stopped, transmitting Count C number of Control Error Packets (CEPs) with Value B. If wireless power transmission has not reduced such that the output current IL is below the current limit value, then enabling an LDO current limit circuit in a power block of the wireless power receiver. In a low-power mode, the receiver enables a hardware over-current circuit that generates an OC INT signal when the output current exceeds a current limit.

Wireless power system

According to some embodiments, a magnetic secured transmission (MST) driver is provided. The MST driver includes a full-bridge switching circuit that includes a first half-bridge coupled to a first node and a second half-bridge coupled to a second node; and a control circuit coupled to drive the first half-bridge according to MST input data and to drive the second half bridge according to a high-frequency pulse width modulation (PWM) signal.

Half-half-bridge pulse width modulation low power magnetic secure transmission systems

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

In accordance with aspects of the present invention, a coil arrangement is presented. A coil arrangement according to some embodiments includes at least one coil positioned to provide a magnetic field in a first area and configured to reduce the magnetic field in a second area outside of the first area. In some embodiments, the at least one coil includes a bent solenoid oriented in the X-Y plane, the bent solenoid localizing magnetic field flux at ends of the bent solenoid. In some embodiments, the bent solenoid can include end caps to further direct the magnetic flux. In some embodiments, the at least one coil includes a flattened solenoid with end caps to direct the magnetic flux. In some embodiments, the coil arrangement is a configuration of multiple coils.

Directed magnetic field coil design

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.

Dynamic deadtime control in a wireless transmission function

According to another embodiment, a system includes a driver circuit that drives a first output and a second output; a coil coupled between the first output and the second output such that the driver circuit drives current through the coil in response to control signals; and a programmable slew circuit coupled to the driver circuit. In some embodiments, a switch is coupled between the first output and the coil. In some embodiments an over-voltage protection circuit is coupled to protect the driver circuit.

Circuits and systems for low power magnetic secure transmission

A capacitor sensor array (or grid) over a wireless power transmission coil can include a first set of lines; a second set of lines intersecting the first set of lines; a first multiplexer coupled to provide a charge (e.g. in the form of a DC voltage) from a voltage source to the first set of lines and provide first signals to detect voltages on each line; and a second multiplexer coupled to provide a charge from the voltage source to the second set of lines and provide second signals to detect voltages on each line, wherein an object positioned with respect to the first set of lines and the second set of lines is located. According to some embodiments, a wireless power receive coil and a rectifier circuit can be used in forming a capacitor sensor, to sense the capacitance between the receive and transmit coils for better alignment between the two coils. Other embodiments are also provided.

Wireless power transmission using a capacitive sensor

In some embodiments, a transmit coil configuration is provided. A coil configuration for a wireless transmitter according to some embodiments can include a plurality of turns coupled between a first tap coupled to an innermost turn and a second tap coupled to an outermost turn; and at least one adjustment tap coupled to at least one turn of the transmitter coil between the innermost turn and the outermost turn. The transmission coil can include an MST coil coupled to the second tap of the transmission coil. In some embodiments, the MST coil can include a plurality of turns arranged in one of a circle, an oval, an egg shape, or a square shape.

Coil design for wireless power transfer

A wireless power circuit is presented that includes a transmit coil coupled to a first node; a receive coil coupled to the first node; a switch circuit coupled to the transmit coil and the receive coil opposite the first node, the switch switching the transmit coil to a second node in a transmit mode and switching the receive coil to the second node in a receive mode; a controller coupled to the first node and the second node, the controller coupled to provide signals to the switch circuit; and a self-start circuit coupled to the receive coil (or Tx coil) that automatically selects one of the coils to be used, the self-start circuit providing power to the switch circuit to hold the switch circuit in the receive mode (or predefined coil to be selected by default).

Wireless power multiple receive coil self-startup circuit for low battery condition

In accordance with embodiments of the present invention, a coil design for the transmission of wireless power. In some embodiments, the coil can include a winding with one or more turns of conductive traces mounted on a substrate, wherein the one or more turns include characteristics that enhance operation of the coil. In some embodiments, the winding includes a transmit coil and a receive coil, each coupled to terminals that provide for a transmit functionality and a receive functionality. In some embodiments, the traces are varied in width and/or thickness in order to optimize the inductance and the coil resistance. In some embodiments, parameters of a control circuit coupled to the coil to affect a transmit functionality or a receive functionality can be optimized.

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San Diego, CA, United States of America

Tao Qi