FEATURES TYPICAL APPLICATION
■ Low Power: ICC = 300µA Typ
■ Designed for RS485 Interface Applications
■ Single 5V supply
■ –7V to 12V Bus Common Mode Range Permits
±7V Ground Difference Between Devices on the Bus
■ Thermal Shutdown Protection
■ Power-Up/Down Glitch-Free Driver Outputs
Permit Live Insertion or Removal of Transceiver
■ Driver Maintains High Impedance in Three-State
or with the Power Off
■ Combined Impedance of a Driver Output and
Receiver Allows Up to 32 Transceivers on the Bus
■ 70mV Typical Input Hysteresis
■ 30ns Typical Driver Propagation Delays
with 5ns Skew
■ Pin Compatible with ±60V Protected LT1785 and
52Mbps LTC1685
APPLICATIONS
■ Low Power RS485/RS422 Transceiver
■ Level Translator
DESCRIPTION
The LTC® 485 is a low power differential bus/line trans-
ceiver designed for multipoint data transmission standard
RS485 applications with extended common mode range
(12V to –7V). It also meets the requirements of RS422.
PACKAGE/ORDER INFORMATION
The CMOS design offers significant power savings over its
bipolar counterpart without sacrificing ruggedness against
overload of ESD damage.
The driver and receiver feature three-state outputs, with
the driver outputs maintaining high impedance over the
entire common mode range. Excessive power dissipation
caused by bus contention or faults is prevented by a
thermal shutdown circuit which forces the driver outputs
into a high impedance state.
The receiver has a fail-safe feature which guarantees a
high output state when the inputs are left open.
The LTC485 is fully specified over the commercial and
extended industrial temperature range.
