Freescale Semiconductor,inc.

Other

Bradley C Stewart

Philip J Sieh

Lawrence Edwin Connell

Pallab Midya

Patrick Lee Rakers

William J Roeckner

Daniel A Mavencamp

William DeWitt McWhorter

Sergio Garcia De Alba Garcin

David L Wilson

Michael A Steffen

Rogelio Reyna Garcia

John L Stewart

Gabriel Sanchez Barba

A microcontroller identifies a maximum x-axis charge time and a maximum y-axis charge time, along with x-axis sensor locations and y-axis that correspond to the maximum charge times (maximum charge time sensor locations). Next, the microcontroller identifies sensor locations that are adjacent to the maximum charge time sensor locations and computes adjacent charge time ratios based upon their corresponding charge times. In turn, the microcontroller uses the largest adjacent charge time ratios and the maximum charge time sensor locations to compute and map an x-axis position and a y-axis position of a user's contact location on a two-dimensional grid.

Capacitive touchpad method using MCU GPIO and signal processing

An electric field sensor may be used to detect accumulation of frozen material. In one embodiment, an e-field system includes a first electrode, a second electrode located at a distance from the first electrode, the second electrode forming a capacitive element with the first electrode, wherein a gap is present between the first and second electrodes, and an electric field sensor having an electrode terminal coupled to the first electrode and providing an electric field output value representative of an amount of frozen material located in the gap between the first and second electrodes. The system may also include a first insulator adjacent the first electrode and outside the gap, and a conductive layer adjacent the first insulator, where the first insulator is between the first electrode and the conductive layer, and where a shield output of the electric field sensor is coupled to the conductive layer.

Frozen material detection using electric field sensor

'Electrical field ('E-field') sensor systems that sense displacement or change in displacement of one body relative to another.' In general, the bodiesare within an electrical field and displacement of a body causes a change in the E-field. A field sensordetects this change and a processortranslates it to a change in position of the displaced body. The E-fields are generated by electrodes (or an electrode and a ground member) that generate the E-field. The systems include detectorsthat detect changes in the E-field, such as capacitance, and transmit these to the processor

Electric field reciprocal displacement sensors

The present disclosure provides several systems. In general, it provides E-field sensor systems that utilize at least one electrodeadapted for creating an E-field in an areawithin a detection volume where fluid presenceor presence of a solid bodyis to be detected. The electrical field sensor is configured to generate a detected signal responsive to a change in capacitance of the electric field, and is communicatively coupled to the electrode. In addition, a processoris configured to determine a quantitative measure of a fluid or solid body within the detection volume in accordance with a capacitive relationship with the detection volume. Described are examples of the system for fluid presence detection, fluid level measurement and measurement of proximity to a solid object.

Electrical field sensors for detecting fluid presence or level

A closed loop audio amplifier system and method of powering up/down the system without producing audible artifacts are provided. During power up, a prebias voltage is provided to each output connected to a speaker to increase the voltage to a nominal output level. High impedance switches are then driven at a 50% duty cycle. Feedback from the output is supplied to a servo, which is enabled to fine tune the output voltage. Low impedance switches are then driven at a 50% duty cycle at a quarter cycle timing. The order of the feedback loop depends on which of the high or low impedance switches are driven. The prebias voltage is then removed before audio signals to be amplified are supplied to the system. Timing of driving of the switches is programmable. To power down, essentially the reverse sequence is provided.

Quiet power up and power down of a digital audio amplifier

A digital-to-analog (D/A) converter for connecting to a computer's parallel port, while allowing another peripheral to be attached to, and use, the same port. The D/A converter requires no external power supply. The D/A converter may be used to produce speech, music or other sounds.

Growing community of inventors

Austin, TX, United States of America

Bradley C Stewart