500 kbps RS-232 transceiver with wide supply tolerance
The Texas Instruments MAX3222ECDBR is a full-duplex RS-232 transceiver in a 20-SSOP package, rated for 500 kbps data rate and operating from a 3V to 5.5V supply. It integrates two drivers and two receivers with 300 mV receiver hysteresis for noise margin on the bus.
Supply voltage and 5V tolerance check
The supply range covers 3V to 5.5V, so the MAX3222ECDBR is natively 5V tolerant on the supply pin. On the logic side, the RS-232 driver outputs swing to the supply rails, and the receiver inputs accept RS-232 levels up to ±25V per the protocol; the logic I/O levels track VCC. If the design runs a 5V rail, this part handles it directly. For 3.3V-only systems, the 3V minimum ensures compatibility without a separate regulator.
