UM3352E_15 Datasheet, PDF (1/13 Pages) Union Semiconductor, Inc. – ESD-Protected, Slew-Rate-Limited, Fail-Safe, True RS-485 Transceivers

UM3352E
±15kV ESD-Protected, Slew-Rate-Limited, Fail-Safe,
True RS-485 Transceivers
General Description
UM3352E SOP8/DIP8
The UM3352E series are ±15kV ESD-protected, high-speed, half-duplex transceivers for RS-485
communication that contain one driver and one receiver. The device features fail-safe circuitry,
which guarantees a logic-high receiver output when the receiver inputs are open, shorted or idle.
This means that the receiver output will be logic high if all transmitters on a terminated bus are
disabled (high impedance). The UM3352E features reduced slew-rate driver that minimizes EMI
and reduces reflections caused by improperly terminated cables, allowing error-free data
transmission up to 500kbps. It also features enhanced ESD protection. All transmitter outputs and
receiver inputs incorporate advanced structures allowing them to survive ESD events in excess of
±15kV Human Body Mode and IEC61000-4-2 Air Discharge Mode, ±8kV IEC61000-4-2 Contact
Discharge Mode. New ESD structures protect the device whether or not it is powered up and
without degrading the RS-485 common mode range of -7V to 12V. The UM3352E includes a hot
swap circuit inside, which allows live cable insertion and removal. Proprietary protection circuit
built on A and B ports, can dissipate high surge current up to 6A to ground.
The transceivers typically draw 450μA of supply current when unloaded, or when fully loaded with
the drivers disabled. The device has a 1/8-unit-load receiver input impedance that allows up to 256
transceivers on the bus and are intended for half-duplex communications.
Applications
Features
 RS-485 Transceivers
 Intelligent Meters and Sensors
 Industrial Control
 Lighting Systems
 Security Systems
 HVAC Application
 ESD Protection for RS-485 I/O Pins
±15kV—Human Body Mode
±15kV—IEC61000-4-2, Air Discharge Mode
±8kV—IEC61000-4-2, Contact Discharge Mode
 True Fail-Safe Receiver
 Enhanced Slew-Rate Limiting Facilitates Error-Free
Data Transmission
 2µA Low-Current Shutdown Mode
 -7V to +12V Common-Mode Input Voltage Range
 Allows up to 256 Transceivers on the Bus
 Thermal Shutdown
 Current-Limiting for Driver Overload Protection
 Hot Swap Capability
Ordering Information
Part Number
Operating
Temperature
UM3352EESA -40°C to +85°C
UM3352EEPA -40°C to +85°C
Mark Code
UM3352EESA
UM3352EEPA
Package Type
SOP8
DIP8
Shipping Qty
2500pcs/13 Inch
Tape & Reel
50pcs/Tube
Device Electrical Characteristic Summary
Part
Number
Guaranteed
Date Rate
(Mbps)
Low-Power
Shutdown
Slew-Rate
Limited
UM3352E
0.5
Yes
Yes
Driver/
Receiver
Enable
Yes
Shutdown
Current
(µA)
2
Transceivers
On Bus
256
±15kV
ESD
Protection
Yes
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http://www.union-ic.com Rev.07 Sep.2015
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