Qualcomm Incorporated

Siemens Healthcare Diagnostics Gmbh

Milind Sawant

Joseph Dale Rutkowski

Shivaprakash Halagur

Liangguo Shen

Joshua Zazzera

Nathaniel Jay T Salazar

Arnold Rudorfer

Steve Magowan

Catalin Tudose

In an aspect, an actuator driver includes a first digital adder configured to output an adjusted control signal based on combining an input control signal and a filtered difference signal, a digital pulse width modulation (PWM) generator configured to convert the adjusted control signal to one or more PWM signals, and an H-bridge amplifier configured to output one or more driving signals based on the one or more PWM signals. The actuator driver further includes a feedback signal generator configured to generate a feedback signal based on the one or more driving signals, a second digital adder configured to output a difference signal based on subtracting the feedback signal from the adjusted control signal, and a loop filter configured to generate the filtered difference signal based on the difference signal.

Actuator driver

In some aspects, a device may comprise a digital modulator to generate a first pulse width modulation (PWM) signal. The device may comprise a first power stage component to generate a first output PWM signal based on the first PWM signal. The device may comprise a first sampling component to sample the first output PWM signal and generate a first sampled output PWM signal. The device may comprise a first adjustment signal generator to generate a first duty cycle adjustment signal based on the first PWM signal and the first sampled output PWM signal. The device may comprise a first PWM adjustment component to adjust a duty cycle of the first PWM signal based on the first duty cycle adjustment signal in association with correcting a duty cycle of the first output PWM signal to generate a corrected first PWM signal. Numerous other aspects are described.

Duty cycle correction

In some aspects, a controller may obtain a back electromotive force (BEMF) signal associated with a haptic feedback component, wherein the BEMF signal is generated by movement of the haptic feedback component. The controller may determine a time length for the BEMF signal to cross an amplitude-based window. The controller may determine, based on the time length, a braking amplitude for a control signal to reduce an energy level of the haptic feedback component. The controller may control the control signal according to the braking amplitude. Numerous other aspects are provided.

Braking control of haptic feedback device

Disclosed are various techniques operating a linear resonant actuator (LRA). In some aspects, a method for operating an LRA includes generating an LRA control signal having a period, the period having an active portion and a high-Z portion according to a duty cycle; detecting, during the high-Z portion of the period, a back electromotive force (BEMF) threshold voltage crossing time and zero voltage crossing time; calculating a period; calculating a BEMF measurement window; calculating a target duty cycle based on the period, the BEMF measurement window, and a margin time; and adjusting the duty cycle of the LRA control signal towards the target duty cycle.

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San Jose, CA, United States of America

Milind Sawant