特点
No Damage or Latchup to ±15kV (Human Body
Model), IEC1000-4-2 Level 4 (±8kV) Contact and
Level 3 (±8kV)
Active Low Carrier Detect Output
Guaranteed High Receiver Output State for
Floating, Shorted or Terminated Inputs with
No Signal Present
Drives Low Cost Residential Telephone Wires
Low Power: I
CC
= 700μA Max with Driver Disabled
I
CC
= 900μA Max in Driver Mode Without Load
20μA Max Quiescent Current in Shutdown Mode
Single 5V Supply
?7V to 12V Common Mode Range Permits ±7V
Ground Difference Between Devices on the Data Line
Maximum Data Rate of 4Mbps
Power Up/Down Glitch-Free Driver Outputs
Up to 32 Transceivers on the Bus
Available in 8-Lead
MSOP
, PDIP and SO Packages
典型应用
描述
描述 The LTC?1482 is a low power RS485 compatible transceiver that offers an active low carrier detect output. The open-drain carrier detect pin allows several transceivers to share the same carrier detect line and can be used to detect the insertion or removal of a driven RS485/RS422 cable. Enhanced ESD protection allows the LTC1482 to withstand ±15kV (human body model), IEC-1000-4-2 level 4 (±8kV) contact and level 3 (±8kV) air discharge ESD without latchup or damage. The LTC1482 receiver stays alive at all times except in shutdown. The supply current is a maximum of 700μA and 900μA when the driver is disabled and enabled respectively. In shutdown, the quiescent current of the LTC1482 drops to a maximum of 20μA. When the driver is disabled or the LTC1482 is in shutdown, the driver outputs are three-stated and remain in a high impedance state over the RS485 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 LTC1482 is fully specified over the commercial and industrial temperature ranges and is available in 8-lead MSOP, PDIP and SO packages.