1 Features
• Operates with 3V to 5.5V VCC supply
• Single-chip and single-supply interface
for IBM™ PC/AT™ serial port
• RS-232 Bus-pin ESD protection of
±15kV Using Human-Body Model (HBM)
• Meets or exceeds the requirements of
TIA/EIA-232-F and ITU V.28 standards
• Three drivers and five receivers
• Operates up to 250kbit/s
• Low active current: 300μA typical
• Low standby current: 1μA typical
• External capacitors: 4 × 0.1μF
• Accepts 5V logic input with 3.3V supply
• Always-active noninverting receiver
output (ROUT2B)
• Operating temperature
– MAX3243C: 0°C to 70°C
– MAX3243I: –40°C to 85°C
• Serial-mouse driveability
• Auto-powerdown feature to disable driver
outputs when no valid RS-232 signal is
sensed

2 Applications
• Battery-powered systems
• Tablets
• Notebooks
• Laptops
• Hand-held equipment

3 Description
The MAX3243 device consists of three line drivers,
five line receivers which is ideal for DE-9 DTE
interface. ±15kV ESD (HBM) protection pin to pin
(serial- port connection pins, including GND). Flexible
power features saves power automatically. Special
outputs ROUT2B and INVALID are always enabled
to allow checking for ring indicator and valid RS232
input.