Mini RS232 to TTL Serial Converter — MAX3232, 3.3V/5V, -40°C to 80°C, Arduino

Mini RS232 to TTL Serial Converter — MAX3232, 3.3V / 5V, -40°C to 80°C

This mini RS232 to TTL serial converter module is based on the Maxim MAX3232 IC, providing bidirectional level conversion between RS232 voltage levels (±12V) and 3.3V or 5V TTL/CMOS logic levels. It enables direct communication between a PC RS232 serial port (DB9) and Arduino, ESP32, STM32, Raspberry Pi, or any UART-capable microcontroller — without risk of damaging 3.3V or 5V logic from RS232's high-voltage swings. Operating from -40°C to +80°C, it is suitable for industrial and outdoor applications.

Key Specifications

Parameter	Value
IC	Maxim MAX3232
Supply Voltage	3.3V or 5V (onboard LDO)
RS232 Voltage	±12V (standard RS232)
TTL Logic Level	3.3V or 5V (compatible)
Channels	2 TX + 2 RX (full duplex)
Max Baud Rate	Up to 1Mbps
RS232 Connector	DB9 female (or header pins)
Operating Temperature	-40°C to +80°C

RS232 vs TTL vs RS485 — Serial Interface Comparison

Feature	RS232	TTL UART	RS485
Voltage Levels	±12V	0–3.3V or 0–5V	±5V differential
Max Distance	15m	<1m	1200m
Topology	Point-to-point	Point-to-point	Multi-drop (32 nodes)
MCU Compatible	❌ (needs converter)	✅ Direct	❌ (needs transceiver)
Best For	PC serial port, legacy equipment	MCU-to-MCU	Industrial multi-node

Why Choose MAX3232 Converter?

• ✅ MAX3232 IC — industry-standard RS232 transceiver, 3.3V and 5V compatible
• ✅ 3.3V / 5V supply — works with Arduino Uno (5V) and ESP32 / STM32 (3.3V)
• ✅ -40°C to +80°C — reliable in industrial and outdoor environments
• ✅ Mini form factor — compact module for space-constrained installations
• ✅ Full duplex — simultaneous TX and RX communication

Typical Applications

• Arduino to PC RS232 serial communication
• ESP32 / STM32 RS232 interface for legacy equipment
• Industrial PLC and HMI RS232 communication
• GPS and GSM module RS232 to TTL conversion
• Barcode scanner and label printer RS232 interface
• Modbus RTU RS232 master/slave communication

Package Contents

• 1 × Mini RS232 to TTL Serial Converter Module (MAX3232)

Enjoy free standard shipping on all orders over $199 USD. Orders are processed within 1–2 business days.

Not satisfied? Return any item within 90 days of purchase for a full refund or exchange. Items must be in original condition.

We are committed to quality, reliability, and customer satisfaction. Every product is carefully selected and tested to meet the highest standards.