【Application Solution】 Say Goodbye to “Blind Brushing”: AWINIC’s Pressure-Sensing Solution Empowers Electric Toothbrushes with “Force Freedom”

2026-04-07

Although electric toothbrushes have long been a part of our daily lives, certain user experience pain points remain difficult to overcome:

“Brush too lightly, and you worry about inadequate cleaning; brush too hard, and you fear damaging your gums.”

This guesswork-based brushing experience introduces uncertainty into daily oral care, not to mention the accompanying issues of noise, splashing, and battery life concerns.

True intelligence should be capable of “sensing” and “protecting.”

The pressure-sensing solution launched by AWINIC enables electric toothbrushes to achieve precise pressure detection and intelligent response. When no pressure is applied, it avoids splashing; when excessive pressure is detected, the system responds immediately, actively adjusting power or issuing a warning, thereby preventing gum damage caused by over-brushing at the source.

01 Pressure-Sensing Application Scenarios for Electric Toothbrushes

Figure 1: Electric Toothbrush Head

1. Pressure-Sensitive Button

The electric toothbrush features one button, with different functions achieved through long and short presses:

· Long press to turn on/off

· Short press to switch modes

2. Pressure Sensing at the Brush Head

· After power-on, if the brush head force is below 30g, it starts with weak activation.

· When the brush head force is between 30g and 200g, the brush head operates normally according to the selected mode.

· If the sensed pressure exceeds 200g, the display or LED shows a “brush head pressure” warning. Simultaneously, the brush head uses intermittent vibration to alert the user and reduces vibration frequency to protect the gums.

3. Other Key Considerations in Applications

· Temperature Compensation: When the ambient temperature changes, the electric toothbrush’s housing structure may become softer or harder, affecting sensor trigger sensitivity. A temperature compensation algorithm is needed to compensate for this and improve user experience.

· Low-Power Solution: For example, in standby mode, the chip intermittently monitors button triggers to save power, ensuring sufficient standby time.

02 AWINIC’s Electric Toothbrush Solutions

To meet the demands of electric toothbrush applications, AWINIC, a leader in analog and mixed-signal ICs, offers two solutions: an AFE solution and an SoC solution.

AFE Solution – AW86872QNR

The AW86872QNR is a high-precision pressure-sensing front-end featuring a 14-bit ADC. It can amplify tiny signals by 256 times, capturing subtle changes in brush head pressure. With a baseline tracking algorithm, it resists temperature drift interference and accurately identifies force differences. Its ultra-low power consumption (4μA) and small package size perfectly suit the compact structure of toothbrushes, meeting both battery life and lightweight requirements.

The AW86872QNR solution is highly cost-competitive, making it tailor-made for electric smart toothbrushes.

Figure 2: AW86872QNR Electric Toothbrush Application Block Diagram

SoC Solution – AW86803QNR

Leveraging the chip’s 60KB flash, customers can integrate the solution. The pressure recognition module no longer requires an additional main controller, enabling direct pressure and button detection. An external motor driver chip can also be connected based on actual needs. When brush head force exceeds the limit or a button is triggered, the motor can be controlled immediately for feedback, significantly boosting development efficiency.

Figure 3: AW86803QNR Electric Toothbrush Application Block Diagram

03 Component Selection

This electric toothbrush circuit solution is designed with a modular approach, incorporating AWINIC’s series of components to ensure stable operation. The overall architecture revolves around three dimensions: power supply – control – interaction.

Table 1: Solution Comparison Table

Power Supply & Battery Management Module – Multi-Layer Protection Design

· AW32002CSR Li-ion battery charging chip supports USB specifications and power path management, compatible with 3.7V Li-ion batteries.

· AW37030D110DNR LDO chip provides 300mA high-performance regulated output to power core components.

· AW33901FCR over-voltage protection chip features 30mΩ low on-resistance and 50ns fast shutdown to protect downstream circuits.

Motor Control

· AW8637DNR driver chip supports 1.9A high-current output and integrates under-voltage, over-current, and over-temperature protection.

Human-Machine Interaction Module

· AW86872QNR button detection chip achieves precise button status recognition with 14-bit precision and low power consumption.

The overall solution balances battery life, performance, and safety, suitable for electric toothbrush products across different positioning levels. The following is a partial component selection table:

Table 2: Component Selection Table

For more details about the solution, please visit:
https://www.awinic.com/cn/applicationDemo?id=1123