DESCRIPTION
The LTC491 is a low power differential bus/line
transceiver designed for multipoint data transmission
standard RS485 applications with extended common mode
range (+12V to–7V). It also meets the requirements
of RS422.
The CMOS design offers significant power savings over
its bipolar counterpart without sacrificing ruggedness
against overload or 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.
Both AC and DC specifications are guaranteed from 0°C to
70℃ and 4.75V to 5.25V supply voltage range.
FEATURES
Low Power: ICC = 300µA Typical
Designed for RS485 or RS422 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 Package
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
28ns Typical Driver Propagation Delays with 5ns
Skew
Pin Compatible with the SN75180
APPLICATION
Low Power RS485/RS422 Transceiver
Level Translator
TYPICAL APPLICATION
Typical Connection
Line Repeater
TEST CIRCUITS
Driver DC Test Load
Driver/Receiver Timing Test Circuit
Receiver Timing Test Load
Driver Timing Test Load
FROM: Company Name: Aunytor Electronic (HK) Co.,Ltd
Contact Person: liao
Skype: Aunytor
Email: 2885745253@qq.com