The MAX3238E/MAX3248E transceivers use Maxim’s revolutionary AutoShutdown Plus™ feature to achieve 10nA supply current. These devices shut down the on-board power supply and drivers when they do not sense a valid signal transition on either the receiver or transmit- ter inputs. This occurs if the RS-232 cable is disconnect- ed or if the transmitters of the connected peripheral are turned off. The devices turn on again when a valid transi- tion 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 addi- tional 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-effi- ciency, dual charge-pump power supply and a low- dropout transmitter combine to deliver true RS-232 performance from a single +3.0V to +5.5V supply. A guaranteed data rate of 250kbps pro
The MAX3238E and MAX3248E are 3 V‑powered RS‑232 transceivers featuring Maxim's AutoShutdown Plus technology, which reduces supply current to 10 nA when no valid signal is present. They provide a guaranteed 250 kbps data rate, five drivers and three receivers, and enhanced ESD protection on both RS‑232 I/O and logic pins, making them suitable for cell‑phone data cables, modems, and other portable equipment.
The devices operate from a supply voltage of +3.0 V to +5.5 V in a 28‑pin SSOP package. They offer low‑level logic thresholds (MAX3248E: 0.6 V–1.2 V) and high‑level thresholds (MAX3238E: 1.1 V–1.2 V). Additional features include a dual charge‑pump voltage converter, FORCEON/FORCEOFF pins for software control, and a non‑inverting R1OUTB output that remains active in shutdown for monitoring purposes.
| Supply Voltage Range | +3.0 V to +5.5 V |
|---|---|
| Data Rate | 250 kbps |
| Supply Current (AutoShutdown) | 10 nA |
| ESD Protection (Human Body Model) | +15 kV |
| Number of Drivers / Receivers | 5 drivers, 3 receivers |
The devices operate from +3.0 V up to +5.5 V.
In AutoShutdown Plus mode the supply current is reduced to 10 nA, and can drop to 1 pA after 30 seconds of inactivity.
The I/O pins are protected up to +15 kV Human Body Model and +8 kV IEC 1000‑4‑2 Contact Discharge.
Each part contains five drivers and three receivers.