Texas Instruments Corporation

Vaibhav Garg

Srinath Mathur Ramaswamy

Lei Ding

Anand Gopalan

Anand Ganesh Dabak

Vijayalakshmi Devarajan

Gangqiang Zhang

Timothy Paul Duryea

Baher S Haroun

Xiaochun Zhao

Angelo W D Pereira

Ultrasonic ranging systems and methods that use coding to distinguish emitted bursts from multiple transducers temporally stagger the bursts emitted from the transducers. The stagger delay between bursts from different transducers in a sensing frame can be randomized between different sensing frames to prevent blind zones. The stagger delay can be relatively small (e.g., between 3 ms and 10 ms) as compared to delays required between bursts in a single-tone ranging system (which would need to be more on the order of between 30 ms and 40 ms, depending on the maximum detecting range of the ranging system). The coding of bursts can be selected to utilize the entire bandwidth of the bursting transducer so as to preserve short-range sensitivity over transducer ringing. Schemes in which some transducers in a system only listen for bursts from other transducers but do not themselves burst within a sensing frame are also described.

Coded ultrasonic sensing with staggered bursts

In an ultrasonic detection system that uses frequency-modulation or phase-modulation coding to distinguish emitted bursts from multiple transducers, a receiver associated with a transducer uses peak search, peak buffer, and peak rank stages in one or more receiver signal processing paths to identify valid received ultrasonic signal envelope peaks in correlator outputs. The peak rank stage can support different modes respectively designed to handle one code, two or more codes, or two or more codes with support for Doppler frequency shift detection. Valid peak information (e.g., amplitude and time) can be reported to a central controller and/or stored locally in a fusion stage to generate more intelligent information for targets or obstacles using peaks from multiple bursts.

Time of flight and code signature detection for coded ultrasonic transmission

In an ultrasonic detection system that uses frequency-modulation coding to distinguish emitted bursts from multiple transducers, a receiver associated with a transducer uses dynamic thresholding to discriminate valid echoes from system and environmental noise in multiple envelope signals produced by multiple correlators. The time-varying dynamic thresholds are generated from the mean of noise in a respective envelope derived from the output of a respective correlator. Multiple thresholds can be combined together such that a single time-varying threshold is applied to all correlators' envelopes. Such thresholding has the benefits of a constant false-alarm rate with regard to detection of echoes (as opposed to false triggering from noise), and, owing to finer-resolution and adaptive thresholds, can detect targets or obstacles as further distances and with greater time responsiveness.

Threshold generation for coded ultrasonic sensing

One example includes a switching power supply. The switching power supply includes a power stage, a feedback loop, and a simulated feedback error generator. The power stage provides an output signal in response to a switching signal. The feedback loop monitors the output signal and provides a feedback error signal to adjust the switching signal to regulate the output signal. The simulated feedback error generator temporarily provides a simulated feedback error signal during a transition period from the low power mode to a high power mode of the switching power supply until the feedback loop has enough time to provide the feedback error signal.

Power supply with low to high power transition mode

The present disclosure describes a channel selector for use in an analog-to-digital converter that has a sampling circuit for converting an analog input to a digital output within a fault tolerance range. The channel selector includes a reception channel, a diagnostic channel, and an impedance compensator. The reception channel receives an analog signal for delivery to the sampling circuit when it is selected for coupling with the sampling circuit. The diagnostic channel receives a diagnostic signal for verifying the digital output of the sampling circuit when it is selected for coupling with the sampling circuit. The impedance compensator is configured to offset a high channel impedance of the reception channel based on the fault tolerance range of the sampling circuit and when the diagnostic channel is selected.

Diagnostic monitoring for analog-to-digital converters

A system including a first power transistor including a gate, a second power transistor including a gate and connected in series with the first power transistor, wherein the connection between the transistors defines a switch node is disclosed. The system further includes a pulse width modulator (PWM) controller configured to assert control signals to the gates of the first and second power transistors, a high side sensing circuit coupled to the gate and a drain of the first power transistor. The system further includes a low side sensing circuit coupled to the gate and a drain of the second power transistor, and a track and hold circuit coupled to the high and low side sensing circuits and configured to couple sense signals from the high and low side sensing circuits.

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Plano, TX, United States of America

Vaibhav Garg