RS232 transceiver — 4/4 driver/receiver complement
The MAX238EWG+ is an RS232 transceiver from Analog Devices, providing four drivers and four receivers in a single 24-SOIC wide-body package (7.50 mm width). It operates in full-duplex mode, meaning the transmit and receive paths are active simultaneously on separate signal pairs — the standard configuration for a DTE-to-DCE serial link. Rated for 120 Kbps data rate, this part targets legacy RS-232 applications such as industrial control panels, test equipment, and point-of-sale terminals where the protocol's ±5V to ±15V swing tolerates noisy cable runs better than lower-voltage serial standards.
No dual positive/negative supplies are needed; the on-chip charge pump generates the RS-232 voltage levels internally.
Receiver hysteresis and noise margin
The receiver input incorporates 500 mV of hysteresis — this built-in noise margin prevents the output from chattering when the cable picks up coupled interference from adjacent motors or switching power supplies. On a long RS-232 run (15 m at 120 Kbps), the hysteresis effectively doubles the noise immunity compared to a zero-hysteresis comparator front-end.
Marked as Active in production with RoHS3 compliance. The 24-SOIC wide-body footprint is shared with several pin-compatible RS232 transceivers in the same family, so a second-source option exists if the supply tightens.