The MAX3237E consists of five line drivers, three line receivers, and a dual charge-pump circuit with ±15-kV ESD protection pin to pin (serial-port connection pins, including GND). The device meets the requirements of TIA/EIA-232-F and provides the electrical interface between an asynchronous communication controller and the serial-port connector. The charge pump and four small external capacitors allow operation from a single 3-V to 5.5-V supply. This device operates at data signaling rates of 250 kbit/s in normal operating mode (MBAUD = GND) and 1Mbit/s when MBAUD = VCC. The driver output slew rate is a maximum of 30 V/µs.
The MAX3237E transmitters are disabled and the outputs are forced into high-impedance state when the device is in shutdown mode (SHDN = GND) and the supply current falls to less than 1 µA. Also, during shutdown, the onboard charge pump is disabled; V+ is lowered to VCC, and V– is raised toward GND. Receiver outputs also can be placed in the high-impedance state by setting enable (EN) high. ROUT1B remains active all the time, regardless of the EN and SHDN condition.
The MAX3237EC is characterized for operation from 0°C to 70°C. The MAX3237EI is characterized for operation from –40°C to 85°C.
