Ambiq Micro, Inc.

Cirrus Logic Inc.

Cirrus Logic International Semiconductor Limited

Yousof Mortazavi

John L Melanson

Aaron J Brennan

Ramin Zanbaghi

Scott McLean Hanson

Ivan Bogue

Daniel Martin Cermak

Ramakanth Kondagunturi

Rajeev Srivastava

Jesse Coulon

Mohammad Ranjbar

Arash Mashayekhi

Aaron Brennan

Ramin Zanbachi

A buck converter may operate in a low power mode or a high power mode based on a power requirements of a load. In the high power mode, modifications to increase frequency response include a higher polling frequency for a comparator, a lower impedance divider in a feedback circuit, a higher biasing current for a comparator, and larger switches for providing current to a reactive step-down circuit of the buck converter. In the low power mode these modifications are reversed. The buck converter may make use of an improved strong arm comparator and a circuit for sensing presence of an inductor in the reactive step-down circuit.

Voltage regulator with high and low power modes

A low-power system-on-chip includes an originating controller, a fabric, and a power controller. The originating controller is configured to initiate a memory transaction request including a source address. The fabric includes an arbiter configured to receive the memory transaction request and determine a first memory device associated with the memory transaction request. The power controller is configured to selectively change a first memory bank of the first memory device from a first power mode to a second power mode based at least in part on the source address. The fabric is configured to perform a memory operation by (a) receiving stored data from memory storage locations corresponding to the source address when the memory transaction request includes a read request, and (b) sending data included in the memory transaction request to the memory storage locations when the memory transaction request includes a program or a write request.

On-demand activation of memory path during sleep or active modes

A system comprises a microcontroller system comprising a CPU, an I/O module, and a microcontroller system power input, a power supply comprising a first power supply output providing power at a first power level, and a second power supply output providing power at a second power level, and a switch comprising a signal input communicatively coupled to the I/O module and configured to receive a status signal from the I/O module, a first switch power input electrically coupled to the first power supply output, a second switch power input electrically coupled to the second power supply output, and a switch power output electrically coupled to the microcontroller system power input and configured to output power to the microcontroller system.

System for providing power to low power systems

In some embodiments, a system comprises a microcontroller system comprising a CPU, an I/O module, and a microcontroller system power input, a power supply comprising a first power supply output providing power at a first power level, and a second power supply output providing power at a second power level, and a switch comprising a signal input communicatively coupled to the I/O module and configured to receive a status signal from the I/O module, a first switch power input electrically coupled to the first power supply output, a second switch power input electrically coupled to the second power supply output, and a switch power output electrically coupled to the microcontroller system power input and configured to output power to the microcontroller system.

Buck converter with inductor sensor

An accelerometer and a linear resonant actuator (LRA) are mechanically coupled, such as by being mounted to the same circuit board. The output of the accelerometer is evaluated in order to select a drive frequency for the LRA. For example, the drive frequency may be varied while measuring the magnitude of acceleration induced by the LRA. The output of the accelerometer may further be used to perform a fitness tracking function, such as counting steps or detecting an activity level.

Low power adaptive linear resonant actuator driver using accelerometer

The dynamic range and power efficiency of a voice-activated system may be improved by dynamically adjusting the configuration of the voice-activated system's input path. In one embodiment, a first portion of audio may be received through an input path of the voice-activated system having a first configuration. A characteristic of the first portion of audio may be determined and the input path may be adjusted to a second configuration based on the determined characteristic. A second portion of audio may then be received through the input path having the second configuration, and speech analysis may be performed on the second portion of audio.

Analog-to-digital converter (ADC) dynamic range enhancement for voice-activated systems

One method of processing microphone input in an ADC to determine microphone configuration is to process the microphone input signals in two processing paths, in which one processing path processes a difference between differential input signals and another processing path processes an average value of the differential input signals. The outputs of these processing paths may be combined to generate a digital signal representative of the analog signal from the microphone. The digital signal contains a digital version of the audio in the environment around the microphone, but may also be used to detect microphone topology and configure aspects of the processing paths to match the detected microphone topology. An apparatus for an ADC may implement the two processing paths as two delta-sigma modulator loops.

Dual processing paths for differential mode and common mode signals for an adaptable analog-to-digital converter (ADC) topology

The overall performance of a dual-path ADC system may be improved by using a VCO-based ADC for small-amplitude signals and employing non-linear cancelation to remove nonlinearities in signals output by the VCO-based ADC. In particular, VCO-based dual-path ADC systems of this disclosure may be configured to receive a first digital signal from a first ADC and a second digital signal from a second ADC, wherein the second digital signal is more non-linear than the first digital signal. The dual-path systems may also be configured to determine one or more non-linear coefficients of the second digital signal based, at least in part, on processing of the first and second digital signals. The dual-path systems may be further configured to modify the second digital signal based, at least in part, on the determined one or more non-linear coefficients to generate a more linear second digital signal.

Non-linearity cancellation in a dual-path ADC

A circuit for a divider or counter may include a frequency divider having multiple rings for dividing an input frequency to obtain an output frequency. The first and second rings may include an odd-numbered plurality of elements, such as inverters, wherein each inverter of a ring is coupled to another inverter of the ring in a circular chain. An input frequency may be input to a power supply input of inverters of the first ring. The second ring inverters may be coupled at a power supply input to output nodes of the first ring inverters, which results in the second ring operating at a divisional rate of the first frequency given by (N&#x2212;1), where N is the number of inverters in the ring. The circuits may be used in frequency dividers and counters, such as in phase-locked loops (PLLs) and analog-to-digital converters (ADCs).

Ring frequency divider

The overall performance of a dual-path ADC system may be improved by using a VCO-based ADC for small-amplitude signals and employing non-linear cancellation to remove nonlinearities in signals output by the VCO-based ADC. In particular, VCO-based dual-path ADC systems of this disclosure may be configured to receive a first digital signal from a first ADC and a second digital signal from a second ADC, wherein the second digital signal is more non-linear than the first digital signal. The dual-path systems may also be configured to determine one or more non-linear coefficients of the second digital signal based, at least in part, on processing of the first and second digital signals. The dual-path systems may be further configured to modify the second digital signal based, at least in part, on the determined one or more non-linear coefficients to generate a more linear second digital signal.

In a switched-power amplifier that has controlled power supply rails, e.g., when a volume control is implemented by varying the power supply voltages, a rate-controlled power supply control circuit eliminates audible pops that would otherwise occur when a change in input level causes the power supply rail voltages to change. The control circuit generates control signals that control the regulators providing the power supply rails with a controlled rate of change such that asymmetry between the voltages of the power supply rail outputs during changes of the power supply rails is substantially reduced. The controlled rate of change is less than or equal to the slowest rate of change of the power supply outputs that supply the power supply rails of the switched-power amplifier.

Growing community of inventors

Austin, TX, United States of America

Yousof Mortazavi