ESP32 Round Display Kit — 2.8 Inch 480×480 MIPI-DSI Capacitive Touch with ESP32-P4X AIBox, Built for AI Devices
An ESP32 round display kit that lights up on the first flash.
The ESP32-P4X AIBox drives a 2.8-inch 480 × 480 round TFT over 2-lane MIPI-DSI, with capacitive touch on I²C. The panel's 30-pin FPC is pin-for-pin compatible with the board's display connector — plug the flex, power up, and the circular UI is on screen. No adapter board, no level shifter, no reverse-engineered init sequence.
Underneath sits the ESP32-P4X: dual-core RISC-V at 400 MHz, 32 MB of PSRAM, 16 MB of flash, and dual-band 2.4 / 5 GHz Wi-Fi 6 through an ESP32-C5. Around it are the parts a finished device needs — MIPI-CSI camera input, an ES8389 audio codec with two microphones and stereo Class-D amplifiers, a MicroSD slot, USB 2.0 High-Speed, a 3-axis accelerometer, and AXP2101 lithium-battery charging. Its AI instruction extensions and FPU run wake-word and vision models on-device through ESP-SR and ESP-DL; the language model stays in the cloud over Wi-Fi 6. One board, two M3 mounting holes, and 480 × 480 as its face.
Key Features
- ESP32-P4X AIBox included — a complete ESP32 display platform — 400 MHz dual-core RISC-V, 32 MB PSRAM, 16 MB flash, Wi-Fi 6, camera, audio, SD card, USB HS and battery management on one board. You are buying a dev kit, not a panel.
- Plug-and-play MIPI-DSI, pin for pin — the panel's 30-pin 0.5 mm flex maps 1:1 onto the board's FPC1 connector, touch I²C lines included. No adapter PCB, no re-wiring, no schematic review.
- 2.8-inch 480 × 480 on a 70.128 mm circle — ST7701S driver, 2-lane MIPI-DSI at 400 Mbps, a 1:1 pixel grid inside the aperture, so dials, gauges and clock faces render without cropping.
- Capacitive touch, integrated on the display flex — TP_INT / SDA / SCL / RST on GPIO27 / 28 / 29 / 26; CST826 or GT911, both supported by the board, no calibration drift.
- ESP-SR voice and ESP-DL vision, on-device — WakeNet wake word, MultiNet offline commands (up to 300), hardware voice activity detection, and INT8 / INT16 vision models on the AI-extended cores, with two analog microphones already wired. No NPU, and no TOPS number printed.
- Camera, audio and sensors already on board — 2-lane MIPI-CSI with SC2336 (1080p30) or OV2710 (720p25) auto-detection, ES8389 codec with two mics, stereo Class-D amplifiers, and an SC7A20 accelerometer for tap or orientation gestures.
- Boots as a working unit — or as a USB-C secondary display — the supplied firmware brings up display, touch, Wi-Fi, SD card, audio and power monitoring; over USB it enumerates on Windows as an extended display with HID touchscreen, no driver install.
- 300 nits, 1200:1, 85° all round, and battery-ready — normally-black IPS in a 2.3 mm, 73.03 × 76.48 mm outline that fits an 80 mm round housing; AXP2101 charging with power path; rated -20 °C to +60 °C.
ESP32-P4X AIBox Board — Specification
Board revision R3, hardware manual V1.0. All GPIO numbers refer to ESP32-P4X GPIOs.
| Item | Specification |
|---|---|
| Board Model | ESP32-P4X AIBox, revision R3 |
| Processor | ESP32-P4X (ESP32-P4 silicon v3.x, ESP32-P4XNRW32); dual-core RISC-V up to 400 MHz + low-power core |
| PSRAM | 32 MB in-package, 200 MHz, HEX mode; supports XIP |
| Flash | 16 MB SPI NOR, DIO mode at 80 MHz |
| Wireless | ESP32-C5-MINI-1-N4; dual-band 2.4 / 5 GHz Wi-Fi 6; SDIO to main processor via ESP-Hosted |
| Display Interface | 2-lane MIPI-DSI; 30-pin, 0.5 mm FPC; SY7200 boost constant-current backlight driver; touch I²C, INT and reset |
| Camera Interface | 2-lane MIPI-CSI; 24-pin, 0.5 mm FPC; onboard 24 MHz clock; 1.8 V / 1.5 V / 3.3 V adjustable rails |
| Supported Camera | SC2336 (1080p30) and OV2710 (720p25), auto-detected at boot |
| Audio | ES8389 codec (I²S + I²C); 2 analog MEMS microphones; 2 × NS4150B Class-D amplifiers; 2 × 1.25 mm speaker connectors |
| Sensor | SC7A20 3-axis accelerometer on I²C, INT1 to main processor |
| Storage | MicroSD slot, 4-bit SDMMC, card detect and power switching |
| USB | 2 × USB Type-C with ESD protection: UART (USB-Serial-JTAG) and USB 2.0 High-Speed OTG (480 Mbps) |
| Power Management | AXP2101; USB 5 V input; single-cell lithium battery (1.25 mm, 2-pin); power button, power LED, charge LED |
| Expansion | 8-pin 1.25 mm (GPIO1–GPIO5, 3.3 V, VSYS, GND); 6-pin 1.27 mm ESP32-C5 debug header |
| Mounting | 2 × M3 mounting holes |
| Development | ESP-IDF v6.1 recommended (min. v5.5.3 for P4 silicon v3.x); esptool v5.3.0 / v4.12.0 or later |
| Default Partition | 16 MB: NVS 24 KB, PHY 4 KB, factory app 6 MB, assets (FAT) ~7.9 MB |
2.8-Inch Round Display — Specification
Model HT028-30MB-A1. Values from the module datasheet, typical at 25 °C unless stated.
| Item | Specification |
|---|---|
| Model No. | HT028-30MB-A1 |
| Display Size | 2.76 inch (marketed as 2.8 inch round) |
| Display Type | a-Si TFT LCD, transmissive, normally black, free viewing angle |
| Resolution | 480 (RGB) × 480 |
| Active Area | 70.128 × 70.128 mm |
| Outline Dimensions | 73.03 (H) × 76.48 (V) × 2.3 (D) mm |
| Colour Depth | 16.7M colours |
| Viewing Angle | 85° / 85° / 85° / 85° (free) |
| Driver IC | ST7701S |
| Interface | 2-lane MIPI-DSI, 30-pin 0.5 mm FPC |
| Touch Panel | Projected capacitive (PCAP), I²C, INT / RST |
| Touch Controller | CST826 or GT911 (module-dependent — confirm on your sample) |
| Luminance | 300 cd/m² (typ.) |
| Contrast Ratio | 1200:1 (typ.), 1000:1 (min.) |
| Response Time | 35 ms (typ.), 40 ms (max.) |
| Backlight | 4 × white LED (1 serial / 4 parallel); Vf 6.6 V typ., If 80 mA |
| Supply Voltage | VCI 2.8 V typ. (2.5–3.6 V); IOVCC 1.8 V typ. (1.65–3.3 V) |
| Operating Temperature | -20 °C to +60 °C |
| Storage Temperature | -30 °C to +80 °C |
| Reliability | 48 h temperature and humidity storage and operation, thermal shock, 76 cm drop, ±6 kV air ESD |
| Compliance | RoHS |
DRAWING & Interface Pin Function
Typical Applications
- AI companion devices and desktop robots — a 70 mm face, two microphones, a speaker, a camera and a battery: wake word local, conversation in the cloud.
- AI voice assistants and smart speakers — a round face for wake word, listening and playback states, with ESP-SR on two onboard mics and stereo Class-D on the output.
- Smart home control panels and thermostat dials — 70 mm of touch surface for temperature rings, scenes and sliders, on Wi-Fi 6.
- AI cameras, doorbells and vision terminals — SC2336 or OV2710 on the CSI port, ISP + PPA pipeline, H.264 in hardware, and local detection when the network is down.
- USB secondary displays for PCs — a dashboard or system-monitor accessory that enumerates as a Windows extended display with touch input.
- Portable instruments and industrial HMI — battery charging, power path and a 400 MHz RISC-V core on one small board, rated -20 to +60 °C.
Variants: kit with board and display, kit plus MIPI-CSI camera, board only, or display only. Datasheet, 2D drawing, 30-pin pinout and the ST7701 init sequence ship with every order. Need 500–1000 nits, a cover lens, a longer FPC or custom firmware? We manufacture both the panel and the board — that is a production change, not a sourcing problem.
Testing DEMO Video for ESP32 round display kit
