The MAX3380E/MAX3381E are +2.35V to +5.5V-powered
EIA/TIA-232 and V.28/V.24 communication interfaces
with low power requirements, high data-rate
capabilities, and enhanced electrostatic discharge
(ESD) protection on both the TTL and RS-232 sides.
The MAX3380E/MAX3381E have two receivers and two
transmitters. All RS-232 inputs, outputs, and logic input
pins are protected to ±15kV using IEC 1000-4-2 Air-Gap Discharge method and the Human Body Model, and ±8kV using IEC 1000-4-2 Contact Discharge
method.
The proprietary low-dropout transmitter output stage
enables true RS-232 performance from a +3.1V to
+5.5V supply with a dual charge pump. The parts
reduce the transmitter output levels to RS-232-compatible
levels with no increase in supply current for supplies
less than +3.1V and greater than +2.35V. The
+2.35V to +5.5V operating range is fully compatible
with lithium-ion (Li+) batteries. The charge pump
requires only four small 0.1µF capacitors for operation.
The MAX3380E/MAX3381E transceivers use Maxim's
revolutionary AutoShutdown Plus™ feature to automatically
enter a 1µA shutdown mode. These
devices shut down the on-board power supply and
drivers when they do not sense a valid signal transition
for 30 seconds on either the receiver or transmitter
inputs.
The MAX3380E is capable of transmitting data at
rates of 460kbps while maintaining RS-232 output
levels, and the MAX3381E operates at data rates up
to 250kbps. The MAX3381E offers a slower slew rate
for applications where noise and EMI are issues. The
MAX3380E/MAX3381E have a unique VL pin that
allows interoperation in mixed-logic voltage systems
down to +1.65V. Both input and output logic levels
are referenced to the VL pin. The MAX3380E/MAX3381E
are available in a space-saving TSSOP package.
Key Features
Applications/Uses
±15kV ESD Protection on All CMOS and RS-232 Inputs and Outputs (Except active-low INVALID)
±15kV Human Body Model
±15kV IEC 1000-4-2 Air-Gap Discharge
±8kV IEC 1000-4-2 Contact Discharge
Operates Over Entire Li+ Battery Range
Low Logic Threshold Down to +1.65V for Compatibility with Cell Phone Logic Supply Voltages