MAX3238E

19-1632; Rev 1; 6/01 +3.0V to +5.5V, 10nA, 250kbps RS-232 Transceivers with ±15kV ESD-Protected I/O and Logic Pins General Description The MAX3238E/MAX3248E transceivers use Maxim’s revolutionary AutoShutdown Plus™ feature to achieve 10nA supply current. These devices shut down the onboard power supply and drivers when they do not sense a valid signal transition on either the receiver or transmitter inputs. This occurs if the RS-232 cable is disconnected or if the transmitters of the connected peripheral are turned off. The devices turn on again when a valid transition is applied to any RS-232 receiver or transmitter input. AutoShutdown Plus automatically achieves this power savings through its on-board circuitry, as no changes are required to the existing BIOS or operating system. All RS-232 inputs and outputs, as well as the logic I/O pins, have enhanced ESD protection to ±15kV. The additional ESD protection on the logic I/O pins makes the MAX3238E/MAX3248E ideal for cell phone data cable applications because it eliminates the need for costly external TransZorb™ or protection schemes. The MAX3238E/MAX3248E contain five drivers and three receivers and are 3V-powered EIA/TIA-232 and V.28/V.24 communication interfaces intended for cell phones, data cables, and modem applications. A proprietary, high-efficiency, dual charge-pump power supply and a lowdropout transmitter combine to deliver true RS-232 performance from a single +3.0V to +5.5V supply. A guaranteed data rate of 25...