Microcontroller State Machine Reduces Watch Actuator Power

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Wearable devices like smart watches experience increased power consumption due to the need for frequent processor wake-ups to operate multiple actuators, such as analogue hands and haptic devices, which reduces battery lifetime.

Innovation Solution

A microcontroller with a state machine and storage medium that generates drive signals autonomously, reducing the need for processor intervention by using a power domain controller and wake-up controller to manage tasks like moving watch hands without waking the processor, thus minimizing power consumption.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Use of energy by moving object

If the processor is used to generate drive signals for multiple actuators, then the actuator control functionality is achieved, but the power consumption increases and battery lifetime decreases

Engineering Contradiction:

Improvepower consumptionVSAvoidbattery lifetime

Core Design Contradiction:

Use of energy by moving objectVSDuration of action of moving object

Solution Approach 1:

The system is divided into two independent controllers: a processor and a state machine. The state machine is segmented off to handle specific actuator control tasks autonomously, allowing the processor to remain in low-power mode while the state machine generates drive signals for actuators based on stored commands and signal profiles.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The state machine is designed to autonomously generate drive signals for actuators without requiring processor intervention. It self-services by executing stored commands, retrieving signal profiles from memory, and directly controlling actuators, thereby eliminating the need for the processor to wake up frequently and reducing overall power consumption.

Inventive Principle:

Principle #25Self-service

2Ease of operation

If the processor wakes up several times per second to operate multiple actuators, then the actuators can be controlled accurately, but the power consumption increases

Engineering Contradiction:

Improveactuator controlVSAvoidpower consumption

Core Design Contradiction:

Ease of operationVSUse of energy by moving object

Solution Approach 1:

The state machine acts as an intermediary between the processor and the actuators. It receives initial configuration from the processor but then independently generates drive signals by executing stored commands and selecting signal profiles from memory, eliminating the need for continuous processor involvement in actuator control operations.

Inventive Principle:

Principle #24Intermediary (Mediator)

Solution Approach 2:

Commands and signal profiles are pre-loaded into the state machine's memory during system initialization or before operation. This preliminary action allows the state machine to autonomously generate drive signals without real-time processor intervention, enabling accurate actuator control while keeping the processor in low-power mode.

Inventive Principle:

Principle #10Preliminary action

Data Source

PatentUS11880314B1Microcontroller for driving an external device

Publication Date: 2024.01.23 DIALOG SEMICONDUCTOR BV

AI summary

A method is provided for using a microcontroller for driving an external device, where the microcontroller comprises a processor coupled to a controller, and the controller comprises a state machine coupled to a storage medium configured to store at least one command executable by the state machine. A drive signal is generated using the controller to drive the external device. The storage medium may be configured by the processor with various commands and waveforms for operating different types of external devices. The proposed microprocessor permits reducing power consumption while at the same time allowing for a broad flexibility of use.