The Unexpected Maker ProS3 u.FL is an ESP32-S3 development board that replaces the chip antenna found on the standard ProS3 with a u.FL connector for an external antenna. That makes it useful when antenna placement is part of the project design. The original u.FL version is no longer stocked at Adafruit; the newer ProS3[D] is its successor and offers both onboard and u.FL antenna options.
What the ProS3 u.FL is
The ProS3 u.FL is a compact development board built around Espressif’s ESP32-S3. Its defining difference from the standard ProS3 is its antenna connection: instead of an onboard chip antenna, the u.FL model lets you connect an external antenna. Make’s January 9, 2024 review notes that this can let a maker choose an antenna suited to a project and mount it away from the microcontroller board.
The ESP32-S3 provides two 32-bit Xtensa LX7 cores, clocked up to 240 MHz, 2.4 GHz Wi-Fi, and Bluetooth 5 with BLE Mesh support. Unexpected Maker lists 16 MB of QSPI flash and 8 MB of QSPI PSRAM on its current ProS3 specification page. These are board specifications, not a guarantee that every application or firmware build can use all memory for the same purpose.
Why choose an external antenna?
An external antenna gives you more flexibility than a fixed antenna on the board: you can choose a compatible antenna and place it where it suits the enclosure or device layout. That can be helpful when the microcontroller needs to sit inside a case or near other components while the antenna is positioned elsewhere. The connector alone does not guarantee better range; results depend on the antenna, its placement, the surrounding materials, and the radio environment.
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- 【ESP32-S3 PERFORMANCE】Dual-core 240MHz processor with 16MB Flash and 8MB PSRAM for IoT, AI, and machine learning projects.
- 【WIRELESS CONNECTIVITY】Onboard antenna for 2.4GHz WiFi and Bluetooth 5.0 LE — for smart home devices, no external antenna needed.
- 【LEAD-FREE GOLD EDITION DESIGN】Immersion gold (ENIG) plating for durability and conductivity. Lead-free, RoHS-compliant — for long-term prototyping.
- 【PRE-SOLDERED, PLUG-IN DESIGN】ESP32-S3 boards come with pre-soldered headers and plug directly into the included expansion and terminal boards — no soldering required.
- 【MULTI-PLATFORM COMPATIBILITY】Works with C++, MicroPython, ESP-IDF, Raspberry Pi, and STM32 — with online tutorials for quick start. Power via USB-C (5V) or VIN pin (5–12V); do not exceed 5V on the USB-C ports.
The u.FL connector is a small board-side connector. Check the antenna connector and cable requirements before ordering, including whether you need a cable that adapts from u.FL to an antenna’s SMA connector. The board’s u.FL version uses an external antenna rather than the standard ProS3’s onboard chip antenna.
Hardware and connections
Unexpected Maker’s ProS3 specifications list 27 GPIO, castellated headers, USB-C, STEMMA QT, an RGB LED, two 3.3 V regulators, and a PicoBlade connector for a LiPo battery. USB-C supports native USB and USB Serial JTAG. The board can charge a LiPo battery through its battery connection.
Rank #2
- High-Performance ESP32-S3 Chip – Powered by the ESP32-S3 processor for fast performance and stable connectivity. Ideal for IoT, AI voice interaction, smart home, robotics, and DIY development projects with extensive open-source support.
- 3.5-Inch Capacitive Touchscreen – Features a 3.5" full-color IPS display with 320×480 RGB565 resolution for clear images and smooth touch control. Perfect for HMI interfaces and interactive applications.
- Rich Expansion Interfaces – Includes multiple interfaces such as IIC and UART for easy connection to sensors, modules, and external devices. Built-in RGB indicator light provides convenient status feedback.
- Audio & TF Card Support – Built-in microphone and external speaker support enable voice input and audio playback. Integrated Micro TF card slot allows convenient storage expansion for multimedia and project files.
- Portable & Easy to Use – Equipped with a USB Type-C port for simple programming and power supply. Supports external lithium battery connection with onboard charging management for safe and portable operation.
The two regulators serve different purposes. Unexpected Maker describes the second 3.3 V LDO as an output for external 3.3 V modules, sensors, and peripherals; it has programmable enable control tied to IO17 and is automatically shut down when the ESP32-S3 enters deep sleep. Check the official board documentation for wiring and power limits before attaching peripherals, since a regulator output is not interchangeable with a general-purpose GPIO pin.
Make listed the board’s dimensions as 2.1 × 0.7 inches in its 2024 review. Confirm the current mechanical drawing before designing a mounting pattern or enclosure around the board.
Rank #3
- Teyleten Robot SuperMini ESP32-S3 Development Expansion Board ESP32 Expansion Edition wifi Bluetooth Expansion Board 3pcs
Programming the board
The ProS3 supports several development workflows. Make describes CircuitPython with UF2 drag-and-drop updates; Adafruit’s older product listing also identifies Arduino IDE, ESP-IDF, and MicroPython as options. Choose firmware and libraries that support the ESP32-S3 and the board’s pinout, then follow the setup instructions for that software environment.
- CircuitPython: the board supports UF2-based drag-and-drop updates.
- Arduino IDE: an option for projects using Arduino libraries and tooling.
- ESP-IDF: Espressif’s development framework for ESP32 applications.
- MicroPython: an additional Python-based route identified in Adafruit’s product information.
ProS3 u.FL versus ProS3[D]
ProS3[D] is the successor product, not a confirmation that the original u.FL model is still sold. Its antenna design is more flexible: it provides an onboard antenna as well as a switchable u.FL option. The comparison below uses only values established in the cited product information; unlisted differences should not be inferred.
Rank #4
- ESP32-S3 Touchscreen Module: 2.8-inch touch serial screen ESP32-S3R8 main control ST7789T3 driver Support communication interface RS485/WiFi/Bluetooth
- 2.8-inch Touch Serial Display, developed based on the ESP32-S3 chip, features a 2.8-inch touchscreen with integrated WiFi and Bluetooth functionality, supporting serial port control. Equipped with an integrated black embedded mounting bracket for easy installation and a sleek, minimalist appearance, it is suitable for smart appliances, smart home systems, industrial instruments, and other applications.
- The esp32 s3 Screen Features a 240x320 resolution color screen with 262K color depth (RGB666), capacitive touch, and wide viewing angles for a smooth interactive experience
- Driver IC:ST7789P3;Touch Chip IC: FT6336U;The esp32-s3 Screen is widely used in energy storage charging equipment, kitchen appliances (such as air fryers, ovens), household appliances (water heaters, washing machines), industrial control products, water quality detectors and other intelligent devices, as well as various scenarios that require LCD color screen display. It is an ideal choice for upgrading traditional segment code screens or black - and - white screens
- High Performance & Low Power Consumption: Equipped with a highly integrated ESP32 - S3 R2 module, it achieves energy - saving and efficient operation through a low - power design
| Feature | Original ProS3 u.FL | ProS3[D] |
|---|---|---|
| Antenna | External antenna via u.FL; no onboard chip antenna, according to Make’s 2024 review. | Onboard antenna and u.FL option, according to Adafruit’s successor product listing. |
| Flash and PSRAM | 16 MB flash and 8 MB PSRAM, per Unexpected Maker’s current ProS3 specification page. | Not stated in the cited successor listing. |
| GPIO | 27 GPIO, per Unexpected Maker’s current ProS3 specification page. | Not stated in the cited successor listing. |
| Battery charging and power | LiPo charging through a PicoBlade connector and two 3.3 V regulators, per Unexpected Maker’s ProS3 specifications. | Not stated in the cited successor listing. |
| Dimensions | 2.1 × 0.7 inches, as listed by Make in 2024. | Not stated in the cited successor listing. |
| Software | CircuitPython, Arduino IDE, ESP-IDF, and MicroPython are identified in the cited product information. | Not stated in the cited successor listing. |
| Availability | Adafruit marks the original product no longer stocked. | Listed by Adafruit as the successor product; availability can change. |
Availability and what to check before buying
Adafruit’s product record for the exact legacy u.FL board, product ID 5749, is marked no longer stocked. Its historical listed price is not a current offer. Adafruit’s ProS3[D] product record, ID 6398, is a separate successor listing; its displayed price and stock can change, so confirm the current product page rather than relying on a past listing.
Quick Recap
Best Value
- ESP32-S3 3.49inch touch LCD development board, equipped with ESP32-S3R8 32-bit LX7 dual-core processor, up to 240MHz main frequency. Supports 2.4GHz Wi-Fi (802.11 b/g/n) and Bluetooth 5 (LE), with onboard antenna. Supports ESP-IDF, Arduino IDE
- Onboard 3.49inch IPS capacitive touch display for clear color picture display, 172 × 640 resolution, 16.7M color. Built-in AXS15231B LCD & touch controller, using QSPI and I2C interfaces for communication respectively
- Equipped with dual microphone array with noise reduction and echo cancellation circuit, suitable for accurate speech recognition and near/far-field wake-up. Onboard audio codec. Supports AI speech interaction
- Built-in 512KB of S-R-A-M and 384KB ROM, with onboard 8MB PSRAM and an external 16MB Flash memory. Onboard TF card slot for extended storage and fast data transfer, suitable for applications such as data recording and media playback
- Onboard QMI8658 6-axis IMU (3-axis accelerometer and 3-axis gyroscope) for detecting motion gestures, counting steps, etc. Onboard PCF85063 RTC chip for RTC functionality. Onboard 3.7V MX1.25 Lithium battery recharge/discharge header
- Confirm the listing is specifically for the external-antenna u.FL version if that is essential to your design.
- For ProS3[D], verify whether the listing and documentation match the antenna arrangement you need.
- Check for a compatible external antenna and any required adapter cable; neither should be assumed included with a board listing.
- Review the pinout, battery connector, power requirements, and mechanical dimensions before integrating the board.
Product prices and availability are accurate as of the date/time indicated and are subject to change. Any price and availability information displayed on Amazon at the time of purchase will apply.
