RS232 Interface using MAX232 ( What is RS232 ? )

What is RS232 ?


In telecommunications, RS-232 is a standard for serial communication transmission of data. It formally defines the signals connecting between a DTE (data terminal equipment) such as a computer terminal, and a DCE (data circuit-terminating equipment or data communication equipment), such as a modem. The RS-232 standard is commonly used in computer serial ports. The standard defines the electrical characteristics and timing of signals, the meaning of signals, and the physical size and pinout of connectors. The current version of the standard is TIA-232-F Interface Between Data Terminal Equipment and Data Circuit-Terminating Equipment Employing Serial Binary Data Interchange, issued in 1997.

An RS-232 serial port was once a standard feature of a personal computer, used for connections to modems, printers, mice, data storage, uninterruptible power supplies, and other peripheral devices. However, RS-232 is hampered by low transmission speed, large voltage swing, and large standard connectors. In modern personal computers, USB has displaced RS-232 from most of its peripheral interface roles. Many computers do not come equipped with RS-232 ports and must use either an external USB-to-RS-232 converter or an internal expansion card with one or more serial ports to connect to RS-232 peripherals. Nevertheless, RS-232 devices are still used, especially in industrial machines, networking equipment, and scientific instruments.

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RS232 Interface using MAX232


MAX3232ESE Datasheet – RS-232 Transceiver Interface IC

Part Number: MAX3232ESE

Function: 3.0V to 5.5V, Low-Power, up to 1Mbps, True RS-232 Transceiver

Package: 16 Narrow SO

Manufacturer: Maxim Integrated


MAX3232ESE datasheet



The MAX3222 / MAX3232 / MAX3237 / MAX3241 transceivers have a proprietary low-dropout transmitter output stage enabling true RS-232 performance from a 3.0V to 5.5V supply with a dual charge pump. The devices require only four small 0.1μF external charge-pump capacitors. The MAX3222, MAX3232, and MAX3241 are guaranteed to run at data rates of 120kbps while maintaining RS-232 output levels. The MAX3237 is guaranteed to run at data rates of 250kbps in normal operating mode and 1Mbps in the MegaBaud™ operating mode.


MAX3232ESE pinout


1. Battery-Powered Equipment
2. Hand-Held Equipment
3. Peripherals
4. Datacom Equipment

Other data sheets are available within the file:

MAX3222C/D, MAX3222EAP, MAX3222EPN ,MAX3222EUP ,MAX3222EWN

MAX3232ESE Datasheet PDF Download

MAX3232ESE pdf