FT232RL USB to TTL UART Serial Adapter Module 5V 3.3V

FT232RL USB to TTL UART Serial Adapter Module — 5V / 3.3V

This FT232RL USB to UART TTL adapter is a compact breakout board built around the genuine FTDI FT232RL USB-to-serial IC. It provides a reliable bridge between your PC’s USB port and any UART/TTL serial device, making it the standard choice for programming Arduino Pro Mini, LilyPad, and other boardless Arduino variants that lack a built-in USB interface.

The key advantage over the FTDI cable is the exposed DTR pin, which enables automatic reset of the target Arduino when a new sketch is uploaded — eliminating the need to manually press the reset button every time.

Specifications

Features

• Original FTDI FT232RL chip — stable, low-latency serial communication
• Compatible with Arduino Pro Mini, LilyPad, and other 6-pin FTDI header boards
• DTR pin exposed — enables auto-reset; no need to press the reset button during upload
• Selectable 3.3V or 5V logic and power via back solder jumper (default: 5V)
• TX and RX indicator LEDs for real-time serial traffic monitoring
• 500 mA self-restore USB fuse for overcurrent protection
• BLK/GRN pin labels matching FTDI cable colour convention (BLK = GND, GRN = CTS)
• Mini USB connector for PC connection
• Standard 2.54 mm pin pitch for breadboard and header compatibility

Wiring to Arduino Pro Mini

3.3V / 5V Selection

The board ships defaulted to 5V. To switch to 3.3V, cut the default trace on the back of the board and bridge the 3.3V solder jumper. This changes both the power output and IO logic levels to 3.3V, making it suitable for 3.3V devices like ESP8266, certain sensors, and other low-voltage modules.

Compatible With

• Arduino Pro Mini (3.3V and 5V variants)
• Arduino LilyPad
• Any board with a 6-pin FTDI header
• ESP8266 ESP-01 (in 3.3V mode)
• General UART/TTL serial devices and microcontrollers
• STC microcontrollers (SCM download)

Driver Installation

FTDI provides signed drivers for Windows, macOS, and Linux. Download the latest VCP (Virtual COM Port) driver from the official FTDI website. On macOS 10.9+ and most modern Linux distributions, the FT232RL is recognised automatically without manual driver installation.

Package Contents

• 1 × FT232RL USB to TTL UART Serial Adapter Module

Note: Mini USB cable not included. If you need to flash an ESP32-CAM, use a CP2102 (5-pin) USB to TTL converter instead — the FT232RL can cause flashing issues with ESP32-CAM.

Frequently Asked Questions

How do I select 3.3V or 5V logic?
Use the onboard jumper/solder pad to choose 5V or 3.3V. Use 3.3V for ESP8266, ESP32 and ESP32-CAM, and 5V for Arduino Pro Mini (5V) boards.

Does it support auto-reset when uploading to Arduino?
Yes. Connect the DTR pin to the target reset line (through a 0.1µF capacitor on Pro Mini) for automatic reset during upload.

Do I need a driver?
Windows 10/11, macOS and Linux usually install the FTDI driver automatically. If not, download the VCP driver from the FTDI website.

Can it flash an ESP32-CAM?
Yes. Set it to 5V power with 3.3V-safe wiring as per the ESP32-CAM guide, connect TX→U0R, RX→U0T, and pull IO0 to GND while powering on.