Application Case: Maxic’s MT3502 Incorporates in VIVO Watch GT

The newly launched VIVO smartwatch, Watch GT has gained considerable popularity due to its eSIM feature and affordable cost. Compared to previous round models from VIVO, the Watch GT presents several advancements, including a refined stainless steel rotating crown, a 2.5D curved large display, new and diverse dials, advanced ball sports navigation, and continuous health monitoring features.

VIVO Watch GT incorporates typical smartwatch components like MEMS microphone, speaker, Bluetooth antenna, four-channel PPG sensor, rotor motor, and Li-ion battery. Its PCB includes wearable chip, eMMC memory, RF transceiver, and charging IC. It also includes a new digital crown for screen scrolling and key functions.

Recently, 52 Audio Network disassembled the VIVO Watch GT smartwatch (click here to view the full report), and Maxic’s MT3502 was found as sensor inside the stainless-steel digital crown. This is the industry's first high-performance, ultra-low-power optical navigation sensor that integrates both rotation and key detections, enabling the control of the digital crown.

MT3502 Overview

Maxic’s MT3502 is the industry's first high-performance, ultra-low-power optical navigation sensor that integrates both rotation and key detections. It incorporates an 850nm VCSEL emitter, an infrared receiver array, a high-precision ADC, and a high-speed digital image processing module. The chip is characterized by its integrated transceiver, high integration, precision, ultra-low power consumption, ease of testing in production, and rich functionality.

MT3502 is based on LASER optical navigation technology, acquiring sequential surface images (frames) through laser reflection and determining the motion via internal algorithm, allowing for real-time, high resolution, high-precision detection of horizontal movement and rotation on stainless steel surface with ultra-low power consumption. It offers a rotation angle resolution of 0.1° and is used for crown rotation and key press detection in smartwatches, smart bands, and smart glasses.

Features:

• First sensor to integrate both rotation and key detection functions

• OLGA package with dimension 3.5mm x 3.2mm x 0.65mm, includes 850nm VCSEL

• Large 24×24 pixel sensing area with a depth of field ranging from 0.5mm to 30mm

• Resolution up to 5000 CPI (on stainless steel surface), supports 900rpm crown rotation speed

• Ultra-low power design

• 550µA (typical) in active mode

• 5µA in sleep mode

• .5µA in standby mode

• Built-in OTP calibration for CPI with accuracy of 0.625%
  

• Supports 1MHz I²C communication with SDA/SCL swap function for dual-device use on the same bus
  

• Supports 2-wire SPI interface
  

• Includes VCSEL fault detection function

Maxic Technology will continue to strive for optimization, upgradation, and product innovation to provide more optimal solutions for the customers.

Feel free to contact us at: sales@maxictech.com