ESP8266 Serial WiFi Module – ESP-WROOM-02U (2MB Flash, 16Mbit, UART Wireless)

Description

Product Overview

The ESP-WROOM-02U is a highly integrated, certified Wi-Fi module developed by Espressif Systems, the original creator of the ESP8266 ecosystem. This module represents the official, production-ready implementation of the ESP8266EX chip, featuring a compact form factor and a U.FL/IPEX connector that allows you to attach an external antenna for enhanced wireless range and flexibility .

What distinguishes the ESP-WROOM-02U from its counterparts (like the ESP-WROOM-02D) is its external antenna interface. While the 02D variant uses a PCB trace antenna, the 02U integrates a U.FL connector, enabling you to choose the optimal antenna for your specific application—whether that’s a high-gain antenna for long-range communication or a flexible antenna for tight enclosures .

At its heart lies the ESP8266EX chip—a Tensilica L106 32-bit RISC processor running at up to 160 MHz, with 2 MB (16 Mbit) of SPI flash memory and 50 kB of user-available SRAM . The module supports 802.11 b/g/n Wi-Fi protocols at 2.4 GHz, delivering up to +20.5 dBm output power and excellent receiver sensitivity down to -98 dBm .

Designed and manufactured by Espressif, the ESP-WROOM-02U comes preloaded with AT command firmware, allowing you to add Wi-Fi connectivity to any microcontroller using simple serial commands. It can also be reprogrammed as a standalone IoT processor using the Arduino IDE, MicroPython, or ESP-IDF.

Key Features

• Official Espressif Module: Designed and manufactured by Espressif Systems, the creators of the ESP8266, ensuring the highest quality and reliable RF performance .

• U.FL/IPEX Antenna Connector: Features an external antenna connector, allowing you to use a high-gain or custom antenna for extended range and flexibility in enclosure design .

• 2 MB Flash Memory: Equipped with 2 MB (16 Mbit) of SPI flash memory, providing sufficient storage for firmware, web interfaces, and OTA (Over-The-Air) firmware updates .

• Integrated 32-bit Processor: Powered by the Tensilica L106 32-bit RISC processor running at up to 160 MHz, capable of running application code independently without an external microcontroller .

• Complete Wi-Fi Solution: Supports 802.11 b/g/n protocols at 2.4 GHz with an external antenna interface. Delivers up to +20.5 dBm output power with receiver sensitivity down to -98 dBm .

• Preloaded AT Command Firmware: Ships with industrial-grade AT firmware that allows control via simple serial commands, enabling rapid integration with any microcontroller.

• Multiple Operating Modes: Supports Station (STA), SoftAP (Access Point), and SoftAP + STA modes, enabling devices to connect to existing networks or create their own .

• Rich Peripheral Interfaces: Provides UART, HSPI, I2C, I2S, IR Remote Control, PWM, and 10-bit ADC interfaces, allowing connection to a wide variety of sensors, actuators, and display devices .

• Ultra-Low Power Consumption: Features multiple sleep modes with deep sleep current as low as 20 µA, making it ideal for battery-powered applications .

• Global Regulatory Certifications: Certified with FCC, CE-RED, TELEC, and RoHS, simplifying the certification process for commercial products .

• Wide Operating Temperature: Rated for operation from -40°C to +85°C, suitable for demanding industrial environments and outdoor installations .

• Compact SMD Package: Measures just 18.0 mm × 14.3 mm × 3.2 mm—the narrow form factor makes it ideal for space-constrained designs .

• Upgradable Firmware: Supports local serial flashing and OTA (Over-The-Air) updates for flexible firmware management.

Technical Specifications