# LILYGO T-Watch 2020 V3 > Programmable ESP32 smartwatch with 1.54-inch touch IPS display, BMA423 accelerometer, PCF8563 RTC, PDM microphone, speaker, IR transmitter, and vibration motor — fully open-source and Arduino/MicroPython programmable. ## Quick Facts - **Brand:** LILYGO - **Board Type:** smartwatch - **Price:** ~$35.29 - **Product Readiness:** developer - **CPU:** Xtensa LX6 dual-core @ 240MHz, FPU, HW crypto (AES/SHA/RSA) - **CPU Architecture:** Xtensa LX6 - **CPU Cores:** 2 - **RAM:** 520KB SRAM - **PSRAM:** 8MB QSPI - **Flash:** 16MB - **USB:** USB-C 2.0 - **Power:** 5V + LiPo - **Operating Voltage:** 3.3V - **Battery:** 2000mAh - **Charging Port:** USB-C - **Antenna:** Built-in PCB antenna - **Display:** 1.54" IPS LCD 240×240 ## Connectivity - **Wifi:** 802.11 b/g/n - **Bluetooth:** BLE 4.2 ## Open Source - **Firmware:** Yes - **Schematics:** No - **PCB Layout:** No ## Compatible Firmware arduino, micropython, platformio ## Use Cases - smart-watch - fitness-tracker - remote-control - voice-assistant - wearable ## Components - **ESP32-D0WDQ6-V3** (mcu): Espressif ESP32-D0WDQ6-V3 dual-core Xtensa LX6 at 240MHz with WiFi and Bluetooth 4.2/BLE. — [Datasheet](https://openhardware.directory/r?to=https%3A%2F%2Fwww.espressif.com%2Fsites%2Fdefault%2Ffiles%2Fdocumentation%2Fesp32_datasheet_en.pdf&ref=openhardware.directory&product=lilygo-t-watch-2020-v3&source=md-export) - **ST7789V** (display-driver): Sitronix ST7789V driving the 1.54-inch 240×240 IPS round-corner display. — [Datasheet](https://openhardware.directory/r?to=https%3A%2F%2Fwww.displayfuture.com%2FDisplay%2Fdatasheet%2Fcontroller%2FST7789.pdf&ref=openhardware.directory&product=lilygo-t-watch-2020-v3&source=md-export) - **FT6336U** (touch-controller): FocalTech FT6336U capacitive touch controller with gesture recognition for the 1.54-inch display. — [Datasheet](https://openhardware.directory/r?to=https%3A%2F%2Ffocusiot.com%2Fwp-content%2Fuploads%2F2018%2F07%2FFT6336U-1.pdf&ref=openhardware.directory&product=lilygo-t-watch-2020-v3&source=md-export) - **BMA423** (accelerometer): Bosch BMA423 3-axis accelerometer with built-in step counter, activity recognition, and wrist-tilt detection. — [Datasheet](https://openhardware.directory/r?to=https%3A%2F%2Fwww.bosch-sensortec.com%2Fmedia%2Fboschsensortec%2Fdownloads%2Fdatasheets%2Fbst-bma423-ds000.pdf&ref=openhardware.directory&product=lilygo-t-watch-2020-v3&source=md-export) - **AXP202** (power-management): X-Powers AXP202 power management IC handling LiPo charging, multiple LDO regulators, and fuel gauge for the watch. — [Datasheet](https://openhardware.directory/r?to=https%3A%2F%2Fgithub.com%2FXinyuan-LilyGO%2FTTGO_TWatch_Library%2Fblob%2Fmaster%2Fdocs%2FAXP202%2520Datasheet%2520v1.0.en.pdf&ref=openhardware.directory&product=lilygo-t-watch-2020-v3&source=md-export) - **MAX98357A** (audio-amplifier): Analog Devices MAX98357A I2S mono amplifier delivering 1W into 8Ω for the onboard speaker. — [Datasheet](https://openhardware.directory/r?to=https%3A%2F%2Fwww.analog.com%2Fmedia%2Fen%2Ftechnical-documentation%2Fdata-sheets%2FMAX98357A-MAX98357B.pdf&ref=openhardware.directory&product=lilygo-t-watch-2020-v3&source=md-export) - **PCF8563** (rtc): NXP PCF8563 I2C real-time clock with alarm function and battery backup for accurate timekeeping. — [Datasheet](https://openhardware.directory/r?to=https%3A%2F%2Fwww.nxp.com%2Fdocs%2Fen%2Fdata-sheet%2FPCF8563.pdf&ref=openhardware.directory&product=lilygo-t-watch-2020-v3&source=md-export) - **IR12-21C** (ir-transmitter): Infrared LED transmitter for sending IR remote control signals at 940nm. — [Datasheet](https://openhardware.directory/r?to=https%3A%2F%2Fwww.everlight.com%2Ffile%2FProductFile%2FIR12-21C-TR8.pdf&ref=openhardware.directory&product=lilygo-t-watch-2020-v3&source=md-export) - **SPM1423HM4H-B** (microphone): Knowles SPM1423HM4H-B PDM MEMS microphone added in V3 for voice capture. — [Datasheet](https://openhardware.directory/r?to=https%3A%2F%2Fwww.knowles.com%2Fdocs%2Fdefault-source%2Fmodel-downloads%2Fspm1423hm4h-b-revb-datasheet.pdf&ref=openhardware.directory&product=lilygo-t-watch-2020-v3&source=md-export) ## Protocols - **SPI**: MOSI: GPIO19, MISO: GPIO2, CLK: GPIO18, CS: GPIO5 - **I2C**: SDA: GPIO21, SCL: GPIO22 - **I2S**: BCLK: GPIO26, LRCK: GPIO25, DATA: GPIO33 ## GPIO Map | Pin | Name | Type | Functions | |-----|------|------|-----------| | GPIO0 | Crown Button / Boot | GPIO | digital-input, strapping | | GPIO2 | SPI MISO | SPI | digital-input | | GPIO5 | SPI CS (Display) | SPI | digital-output | | GPIO8 | IR Transmitter | GPIO | digital-output, pwm | | GPIO12 | Free GPIO / Touch CS | GPIO | digital-input, digital-output, adc | | GPIO18 | SPI CLK | SPI | digital-output | | GPIO19 | SPI MOSI | SPI | digital-output | | GPIO21 | I2C SDA | I2C | digital-input, digital-output | | GPIO22 | I2C SCL | I2C | digital-output | | GPIO25 | I2S LRCK | I2S | digital-output | | GPIO26 | I2S BCLK | I2S | digital-output | | GPIO33 | I2S DATA | I2S | digital-output | | GPIO34 | Vibration Motor | GPIO | digital-output | ## Description ## Overview The LILYGO T-Watch 2020 V3 is a fully programmable smartwatch built on the Espressif ESP32, offering a rich set of integrated peripherals for both practical wearable applications and hardware experimentation. The 1.54-inch IPS display with capacitive touch support provides a responsive interface for custom watch faces, fitness dashboards, and notification displays. Version 3 adds a PDM microphone for voice applications and integrates a MAX98357A I2S amplifier driving an 8Ω speaker — enabling audio playback, alarms, and basic voice interaction. The BMA423 three-axis accelerometer with built-in step counter supports fitness tracking, gesture detection, and wrist-tilt wake. The AXP202 power management IC handles LiPo charging and power rail distribution across the display, sensors, and radio. Additional hardware includes a PCF8563 RTC for accurate timekeeping across power cycles, an infrared transmitter for controlling TVs and appliances, and a vibration motor for notifications. With 16MB flash, 8MB PSRAM, WiFi, and Bluetooth, the T-Watch 2020 V3 runs MicroPython, Arduino, or the dedicated T-Watch library. ## Where to Buy - [LILYGO Official](https://openhardware.directory/r?to=https%3A%2F%2Flilygo.cc%2Fproducts%2Ft-watch-2020-v3&ref=openhardware.directory&product=lilygo-t-watch-2020-v3&source=md-export) — $35.29 ## Resources - [product](https://openhardware.directory/r?to=https%3A%2F%2Flilygo.cc%2Fproducts%2Ft-watch-2020-v3&ref=openhardware.directory&product=lilygo-t-watch-2020-v3&source=md-export) - [github](https://openhardware.directory/r?to=https%3A%2F%2Fgithub.com%2FXinyuan-LilyGO%2FTTGO_TWatch_Library&ref=openhardware.directory&product=lilygo-t-watch-2020-v3&source=md-export) - [wiki](https://openhardware.directory/r?to=https%3A%2F%2Fwiki.lilygo.cc&ref=openhardware.directory&product=lilygo-t-watch-2020-v3&source=md-export) ## Tags `esp32`, `smartwatch`, `wearable`, `lilygo`, `ttgo`, `touch`, `accelerometer`, `rtc`, `speaker`, `microphone` ## Images ![LILYGO T-Watch 2020 V3](https://nbg1.your-objectstorage.com/openhardware-directory/entities/lilygo-t-watch-2020-v3/a0f7ad4b7b04.jpg) ![LILYGO T-Watch 2020 V3](https://nbg1.your-objectstorage.com/openhardware-directory/entities/lilygo-t-watch-2020-v3/cf3be6cc0642.jpg) ![LILYGO T-Watch 2020 V3](https://nbg1.your-objectstorage.com/openhardware-directory/entities/lilygo-t-watch-2020-v3/4dbcead8f2d7.jpg) ![LILYGO T-Watch 2020 V3](https://nbg1.your-objectstorage.com/openhardware-directory/entities/lilygo-t-watch-2020-v3/774041bdc733.jpg) ![LILYGO T-Watch 2020 V3](https://nbg1.your-objectstorage.com/openhardware-directory/entities/lilygo-t-watch-2020-v3/5f1b830796be.jpg) ![LILYGO T-Watch 2020 V3](https://nbg1.your-objectstorage.com/openhardware-directory/entities/lilygo-t-watch-2020-v3/9b826d22a44a.jpg) ![LILYGO T-Watch 2020 V3](https://nbg1.your-objectstorage.com/openhardware-directory/entities/lilygo-t-watch-2020-v3/a1abd8d34b5b.jpg) ![LILYGO T-Watch 2020 V3](https://nbg1.your-objectstorage.com/openhardware-directory/entities/lilygo-t-watch-2020-v3/4800883ac316.png) > **Battery Powered:** Li-Po --- [View full device page](https://openhardware.directory/devices/lilygo-t-watch-2020-v3)