# Wi-Fi & Bluetooth FCM266D

## Summary

- Wi-Fi 6 and BLE 5.4 module
- LCC form factor
- 20.0mm × 18.0mm × 2.4mm
- Approx. 1.23g
- Operating temperature range: -40°C to +85°C

## Key features

- Wi-Fi 6 module, single band (2.4GHz), 1×1 antenna
- BLE 5.4 and Bluetooth-assisted Wi-Fi provisioning
- Built-in 640KB SRAM and 4MB flash
- Supports up to 21 GPIOs under the QuecOpen® solution, providing multiple peripheral interfaces
- 1st generation RF coaxial connector, pin antenna interface, PCB antenna (optional)
- Wide operating temperature range: -40°C to +85°C

## Overview

The FCM266D is a cutting-edge MCU Wi-Fi and Bluetooth module launched by Quectel. It boasts a high-performance ARMv8-M Star MCU processor with a frequency of up to 240MHz and supports IEEE 802.11 b/g/n/ax protocol and BLE 5.4. The module features built-in 640KB SRAM and 4MB flash, ensuring efficient performance.

The module complies with WPA-PSK, WPA2-PSK and WPA3-SAE security standards, supports TRNG (True Random Number Generator) and AES/RSA/SHA/ECC encryption algorithm. The module is in LCC form factor with an ultracompact package size of 20.0mm x 18.0mm x 2.4mm, which optimizes the size and cost for end-products and is compatible with diverse designs.

The FCM266D supports UART, SPI, I2C, ADC, PWM interfaces by default, and supports SDIO interface in QuecOpen® solution, and many low power consumption modes and keep-alive mechanism, which provides flexibility and versatility for a range of applications, especially in smart homes and industrial IoT scenarios. Thanks to its high processor frequency and Wi-Fi 6 protocol, the module is particularly suitable for application scenarios such as photovoltaics and energy storage which require high-speed commands and low-latency data transmission.

The module supports QuecOpen® solution and standard AT commands, with a compact protocol, and can realize efficient product development for customers.

## Product Brochure

[Quectel_Product_Brochure_V8.6.pdf](https://www.quectel.com/content/uploads/2026/05/Quectel_Product_Brochure_V8.6.pdf)

## Documentation and resources

### Hardware Development Resources

- [Quectel_FCM266D_Hardware_Design_V1.0](https://www.quectel.com/login/?redirect=https%3A%2F%2Fwww.quectel.com%2Fproduct%2Fwi-fi-bluetooth-fcm266d%2F) - File Size: 2.03 MB
- [Quectel_FCM266D_2D_Dimensions_V1.1](https://www.quectel.com/login/?redirect=https%3A%2F%2Fwww.quectel.com%2Fproduct%2Fwi-fi-bluetooth-fcm266d%2F) - File Size: 132.12 KB
- [Quectel_FCM266D_3D_Dimensions_V1.1](https://www.quectel.com/login/?redirect=https%3A%2F%2Fwww.quectel.com%2Fproduct%2Fwi-fi-bluetooth-fcm266d%2F) - File Size: 343.21 KB
- [Quectel_FCM266D_Footprint&Part_V1.2](https://www.quectel.com/login/?redirect=https%3A%2F%2Fwww.quectel.com%2Fproduct%2Fwi-fi-bluetooth-fcm266d%2F) - File Size: 729.61 KB

### User Guide

- [Quectel_FCM266D_QuecOpen(SDK)_General_API_Development_Guide_V1.0](https://www.quectel.com/login/?redirect=https%3A%2F%2Fwww.quectel.com%2Fproduct%2Fwi-fi-bluetooth-fcm266d%2F) - File Size: 1.22 MB
- [Quectel_FCM266D_TE-B_User_Guide_V1.0](https://www.quectel.com/login/?redirect=https%3A%2F%2Fwww.quectel.com%2Fproduct%2Fwi-fi-bluetooth-fcm266d%2F) - File Size: 1.50 MB

Have a question? [Contact us](https://www.quectel.com/product/wi-fi-bluetooth-fcm266d#contact)

## Also of interest

- [Why certification must take a global approach](https://www.quectel.com/blog/global-device-certification/)
- [Digital signage](https://www.quectel.com/industry/digital-signage/)
- [RTK Correction Solution](https://www.quectel.com/gnss-rtk-correction-solution/)