**ADM208EARZ: A Complete Guide to the 5V RS-232 Transceiver**

The ADM208EARZ is a robust, high-performance **5V-powered RS-232 transceiver** from Analog Devices, designed to facilitate reliable serial communication in electrically noisy environments. As a cornerstone of many legacy and modern industrial, networking, and embedded systems, this integrated circuit (IC) provides a vital link between a UART (Universal Asynchronous Receiver/Transmitter) and the RS-232 physical interface.

Housed in a compact 20-pin SOIC_W package, the ADM208EARZ is a complete solution, integrating **four transmitters and five receivers**, with one receiver dedicated to always monitoring the Ring Indicator (RI) signal. This configuration is exceptionally well-suited for multi-channel communication applications, such as in modems or serial port cards, where multiple data and control signals must be handled simultaneously.

A key feature of this transceiver is its compliance with the stringent **EIA-232E and V.28/V.24 communication protocols**. It is engineered to operate with a single +5V power supply, greatly simplifying system design by eliminating the need for costly and bulky dual ±12V power supplies. Internally, the device utilizes an efficient on-chip charge-pump voltage converter to generate the necessary positive and negative voltages required to deliver true RS-232 compliant ±5.0V output levels, ensuring signal integrity over longer cable lengths.

The **on-board charge pump** requires only four small external 0.1µF capacitors to operate, minimizing the bill of materials and board space. With a maximum data rate of **up to 460kbps**, the ADM208EARZ comfortably supports standard baud rates from 9600 up to 115200 and beyond, making it compatible with a vast array of devices and protocols.

Furthermore, the ADM208EARZ is designed for robustness. It features **ESD protection of up to ±15kV** on all transmitter outputs and receiver inputs (using the Human Body Model). This high level of electrostatic discharge protection is critical for safeguarding the IC and the more sensitive system components downstream from voltage spikes commonly encountered during hot-plugging or in harsh industrial environments.

**ICGOOODFIND:** The ADM208EARZ stands out as a highly integrated, reliable, and efficient solution for multi-channel RS-232 communication. Its combination of a single 5V supply operation, robust ESD protection, and a complete feature set makes it an excellent choice for designers modernizing or maintaining systems that depend on this enduring serial communication standard.

**Keywords:** RS-232 Transceiver, 5V Power Supply, ESD Protection, Charge Pump, EIA-232E Compliance