The MAX232DR from Texas Instruments is a dual driver/receiver that includes a capacitive voltage generator to supply TIA/EIA-232-F voltage levels from a single 5-V supply. It is a popular choice for converting TTL/CMOS signal levels to RS-232 levels and vice versa.

The MAX232DR is capable of operating at data rates up to 120 kbit/s, making it suitable for a wide range of applications, such as:

• Serial port communication between computers and peripherals
• Industrial automation and control systems
• Telecommunications equipment
• Point-of-sale systems
• Medical devices

The MAX232DR is also highly robust, with ESD protection exceeding JESD 22 and ±30-V input levels. This makes it ideal for use in harsh environments where noise and interference are common.

Features

• Meets or exceeds TIA/EIA-232-F and ITU Recommendation V.28
• Operates from a single 5-V power supply
• Operates up to 120 kbit/s
• Two drivers and two receivers
• ±30-V input levels
• Low supply current: 8 mA typical
• ESD protection exceeds JESD 22

Applications

• Serial port communication between computers and peripherals
• Industrial automation and control systems
• Telecommunications equipment
• Point-of-sale systems
• Medical devices

Description

The MAX232DR is a dual RS-232 driver/receiver that is commonly used to convert TTL/CMOS signal levels to RS-232 levels and vice versa. It operates from a single 5-V power supply and can operate at data rates up to 120 kbit/s.

The MAX232DR includes a capacitive voltage generator to supply TIA/EIA-232-F voltage levels from the single 5-V supply. This eliminates the need for external voltage converters, making the MAX232DR a simple and easy-to-use solution for RS-232 interfacing.

The MAX232DR also features ESD protection exceeding JESD 22 and ±30-V input levels. This makes it ideal for use in harsh environments where noise and interference are common.

The MAX232DR is typically used in applications such as serial port communication between computers and peripherals, industrial automation and control systems, telecommunications equipment, point-of-sale systems, and medical devices.

How to use the MAX232DR

The MAX232DR is a relatively easy-to-use device. It has four TTL/CMOS input pins (IN1+, IN1-, IN2+, and IN2-) and four RS-232 output pins (OUT1+, OUT1-, OUT2+, and OUT2-).

To use the MAX232DR, simply connect the TTL/CMOS input pins to the TTL/CMOS signals that you want to convert to RS-232 levels. Then, connect the RS-232 output pins to the RS-232 device that you want to communicate with.

The MAX232DR also has two power supply pins (VCC and GND). Connect the VCC pin to a 5-V power supply and the GND pin to ground.

Example circuit

The following circuit shows how to use the MAX232DR to convert TTL/CMOS signal levels to RS-232 levels:

MAX232DR circuit

In this circuit, the TTL/CMOS signals from the microcontroller are connected to the IN1+ and IN1- pins of the MAX232DR. The RS-232 output pins of the MAX232DR are connected to the RS-232 device that you want to communicate with.

The VCC pin of the MAX232DR is connected to a 5-V power supply and the GND pin is connected to ground.

Conclusion

The MAX232DR is a versatile and easy-to-use device for RS-232 interfacing. It is suitable for a wide range of applications, from simple serial port communication to complex industrial control systems.