Abstract: A determination is made as to whether touch pressure data acquired from each of a plurality of touch pressure sensors is indicative of abnormal operation. If abnormal operation is indicated, the touch pressure data from each of the plurality of touch pressure sensors, except those touch pressure sensors having touch pressure data indicative of abnormal operation, is summed. Then, the sum is multiplied by a correction factor to produce a touch pressure output indicative of physical force applied to the plurality of touch pressure sensors.

Abstract: An integrated circuit is provided having an active circuit. A heating element is adjacent to the active circuit and configured to heat the active circuit. A temperature sensor is also adjacent to the active circuit and configured to measure a temperature of the active circuit. A temperature controller is coupled to the active circuit and configured to receive a temperature signal from the temperature sensor. The temperature controller operates the heating element to heat the active circuit to maintain the temperature of the active circuit in a selected temperature range.

Abstract: A power transmitter includes: a first switch coupled between a first node and a reference voltage node; a second switch configured to be coupled between a power supply and the first node; a coil and a capacitor coupled in series between the first node and the reference voltage node; a first sample-and-hold (S&H) circuit having an input coupled to the first node; and a timing control circuit configured to generate a first control signal, a second control signal, and a third control signal that have a same frequency, where the first control signal is configured to turn ON and OFF the first switch alternately, the second control signal is configured to turn ON and OFF the second switch alternately, and where the third control signal determines a sampling time of the first S&H circuit and has a first pre-determined delay from a first edge of the first control signal.

Abstract: A power transmission system includes at least one wireless power transmission circuit. A first wireless power reception circuit includes a first circuit comparing a reference voltage to a feedback voltage representing an output voltage produced from received power and delivered to an output node, and adjusting a first control terminal of a device supplying a first rectified voltage until the feedback and reference voltages are equal. A second wireless power reception circuit includes a second circuit modifying a control terminal of a device sourcing a second rectified current produced from received power to the output node, based upon comparison of a reference current to a current representative of the second rectified current. Control circuitry adjusts the reference current until a first rectified voltage generated by the first wireless power reception circuit and a second rectified voltage generated by the second wireless power reception circuit are equal.

Abstract: An over-voltage protection circuit and methods of operation are provided. In one embodiment, a method includes monitoring a voltage at an output of a rectifier, a voltage at an output of a voltage regulator, or a combination thereof. The method further includes determining the over-voltage condition based on the monitoring; and in response to determining the over-voltage condition, regulating the voltage at the output of the rectifier in accordance with a voltage difference between the voltage at the output of the rectifier and the voltage at the output of the voltage regulator.

Abstract: A data frame in a touch capacitive sensing circuit includes both mutual capacitance data and self capacitance data. The mutual capacitance data and self capacitance data of the frame are filtered to define mutual capacitance and self capacitance islands. Centroids of the mutual capacitance and self capacitance islands are calculated and then processed in a weighted mixing operation to produce a hybrid centroid that more accurately locates the coordinates of a detected touch/hover.

Abstract: A touch screen controller disclosed herein includes a circuit configured to generate a digital touch voltage comprises of samples, at a base sampling rate. The touch screen controller also includes a digital processing unit configured to analyze a first subset of samples of the digital touch voltage samples to determine noise content thereof, the first subset of samples corresponding to samples at a first investigated sampling rate that is a first function of the base sampling rate. The digital processing unit is also configured to analyze a second subset of samples of the digital touch voltage to determine noise content thereof, with the second subset of samples corresponding to samples at a second investigated sampling rate that is a second function of the base sampling rate, and determine a preferred sampling rate from among the first and second investigated sampling rates as a function of determined noise content thereof.

Abstract: Disclosed herein is a circuit including a driver circuit applying a received drive signal to a capacitive sensing line of a capacitive touch panel as a boosted drive signal, the driver circuit powered by a boosted supply voltage. A charge pump circuit receives an input supply voltage and output the boosted supply voltage, the charge pump circuit including a voltage sensing circuit to sense the boosted supply voltage and a comparison circuit to compare the sensed boosted supply voltage to a threshold and produce a comparison signal. A control circuit determines a ratio of a pulse width of the comparison signal to the drive signal, and tunes operation of the charge pump circuit to drive the ratio to match a performance threshold.

Abstract: In an embodiment, an image sensor includes: first and second voltage rails; first and second regulators configured to generate first and second regulated voltage at the first and second voltage rails, respectively; and a plurality of pixels coupled to the first and second voltage rails. Each pixel includes: first and second transistor coupled first and second storage capacitor, respectively. A third transistor is coupled between a control terminal of the first transistor and the first or second voltage rails. The third transistor is configured to limit a slew rate of current flowing between the control terminal of the second transistor and the first or second voltage rails to a first slew rate when the image sensor operates in global shutter mode, and to a second slew rate when the image sensor operates in rolling mode, the first slew rate being smaller than the second slew rate.

Abstract: A touch screen controller (TSC) performs mutual capacitance sensing to acquire touch strength values from a touch matrix formed by capacitively intersecting drive and sense lines. For each sense line, the TSC sums the touch strength values associated therewith to form an emulated value for that sense line, and applies a weighting thereto, the weighting based upon a position of that sense line compared to a location on the touch matrix adjacent which a user's ear is expected to be placed. For each drive line, the TSC sums the touch strength values associated therewith to form an emulated value for that drive line, and applies a weighting thereto, the weighting based upon a position of that drive line compared to the location on the touch matrix adjacent which the user's ear is expected to be placed. The TSC determines presence of the user's based upon the emulated values.

Abstract: Disclosed herein is a method of operating a touch screen controller in a device with a touch screen having force lines and sense lines. The method includes receiving touch data from the touch screen, and operating the touch screen in a self capacitance sensing mode. In the self capacitance sensing mode, which force lines have strength values indicating a potential touch to the touch screen are determined. The method also includes operating the touch screen in a mutual capacitance sensing mode, and in the mutual capacitance sensing mode, performing mutual capacitance sensing on only a subset of the force lines, with the subset of the force lines including at least those force lines indicating the potential touch to the touch screen.

Abstract: A low drop-out (LDO) voltage regulator circuit includes a power transistor having a control terminal configured to receive a control signal and an output terminal coupled to an output node. A current regulation loop senses current flowing through the power transistor and modulates the control signal to cause the power transistor to output a constant current to the output node. A voltage regulation loop senses voltage at the output node and modulates the control signal to cause the power transistor to deliver current to the output node so that an output voltage at the output node is regulated. The current regulation loop includes a bipolar transistor connected to the control terminal of the power transistor, where a base terminal of the bipolar transistor is driven by a signal dependent on a difference between the sensed current flowing through the power transistor and a reference.

Abstract: A receiver circuit includes a rectifier operable in full-, half-synchronous and asynchronous modes. A measurement circuit, with method, provides for real-time power measurement within the rectifier. The measurements are made based on the average output current from the rectifier delivered to the load and measurements sampled over time of the instantaneous voltage at each input/output node of the rectifier. Equivalent resistance in the rectifier is determined from the measurements and power dissipation calculated from the determined equivalent resistance and the average output current. The instantaneous voltages are synchronously captured through high-voltage AC coupling in order to detect the voltage drop across each element of the rectifier. The sensed voltages are amplified in the low voltage domain and converted by a high-speed analog-to-digital converter in order to produce data useful in computing equivalent resistance values.

Abstract: A high-side switching transistor of a rectifier circuit is driven by a high-side driver circuit to supply current to an output node. The high-side driver circuit is powered between a capacitive bootstrap node and the output node. A boot charge circuit charges the bootstrap capacitor by supplying current to the bootstrap node. The boot charge circuit includes: a first current path that selectively supplies a first charging current to the bootstrap node when the rectifier circuit is operating in a switching mode; and a second current path that selectively supplies a second charging current to the bootstrap node when the rectifier circuit is operating in a reset mode.

Abstract: A system comprising includes a wireless power receiver generating a rectified voltage. A low dropout regulator (LDO) generates a first regulated output voltage from the rectified voltage, during a first phase. A first switch couples the first regulated output voltage to a voltage output node during the first phase. During a second phase, the LDO generates a second regulated output voltage from the rectified voltage. A switching regulator generates a third regulated output voltage during the second phase. A second switch couples the third regulated output voltage to the voltage output node during the second phase. During a third phase, the LDO is disabled, while the switching regulator continues to generate the third regulated output voltage. The first switch opens during the third phase while the second switch remains closed.

Abstract: A wireless power receiving circuit includes a transistor based rectifier receiving an AC input voltage, and control logic receiving an overvoltage signal. The control logic generates control signals for controlling turn on of transistors within the transistor based rectifier based upon the overvoltage signal so as to cause the transistor based rectifier to produce a rectified output voltage from the AC input voltage. A comparator compares the rectified output voltage to a reference voltage and asserts the overvoltage signal if the rectified output voltage is greater than the reference voltage. In response to assertion of the overvoltage signal, the control logic asserts the control signals to simultaneously turn on all transistors of the transistor based rectifier.

Abstract: The half-bridges driving a multiphase motor are controlled to perform a sequence of operations to support charging a hold capacitor. First, in a brake configuration, the half-bridge transistors are controlled such that either high-side transistors or low-side transistors of the half-bridges are turned on. Second, in an active step-up configuration, the half-bridge transistors are controlled such that the high-side transistor of a first half-bridge and the low-side transistor of a second half-bridge are both turned on and the low-side transistor of the first half-bridge and the high-side transistor of the second half-bridge are both turned off. Third, in an active brake configuration, the half-bridge transistors are controlled such that the low-side transistor of the first half-bridge and the high-side transistor of the second half-bridge are both turned on and the high-side transistor of the first half-bridge and the low-side transistor of the second half-bridge stage are both turned off.

Abstract: In one embodiment, a method for operating an electronic device includes determining that a touch sensitive display is being contacted. The touch sensitive display includes a plurality of mutual-sensing capacitive sensor regions and an array of self-sensing capacitive sensor regions. The plurality of mutual-sensing capacitive sensor regions is arranged in rows and columns on the touch sensitive display. The array of self-sensing capacitive sensor regions is arranged in a row or a column on the touch sensitive display. The method may include obtaining mutual sensing touch values for each of the rows and the columns and self-sensing touch values for the row or the column. Based on the mutual sensing touch values and self-sensing touch values, the method includes determining whether a contacted region of the touch sensitive display is an impression of a single finger, multiple fingers, a single thumb, or multiple thumbs.

Abstract: A capacitive sensing structure includes a first sensing electrode located in a first layer for sensing a first capacitance and producing a first sense signal indicative of the sensed first capacitance. A transmit electrode is located in the first layer and positioned surrounding 90%+ of a perimeter of the first sensing electrode. A second sensing electrode is located in the first layer and positioned surrounding 90%+ of a perimeter of the transmit electrode, the second sensing electrode to sense a second capacitance and produce a second sense signal indicative of the sensed second capacitance. Controller circuitry receives the first and second sense signals, compares a change in the sensed first capacitance to a change in the sensed second capacitance, and produces an output signal indicative of a user touch based upon the comparison between the change in the sensed first capacitance and the change in the sensed second capacitance.

Abstract: A touch screen controller includes driving circuitry coupled to a conductive line through a resistance and drives that conductive line with a driving signal passed through the resistance at a drive frequency. Sensing circuitry is coupled to that conductive line and senses a voltage at that conductive line, the voltage being a function of a capacitance seen by that conductive line. Analog to digital conversion circuitry is coupled to the sensing circuitry and samples the sensed voltage at a sampling frequency to produce samples. Processing circuitry is coupled to the analog to digital conversion circuitry and directly calculates a tangent of a phase shift of the voltage due to the resistance and the capacitance from the samples, and determines a self touch value for that conductive line as a function of the tangent of the phase shift of the voltage.