LTC2857 - 20Mbps and Slew Rate Limited 15kV RS485/RS422 Transceiver

The LTC2856-1, LTC2856-2, LTC2857-1, LTC2857-2, LTC2858-1 and LTC2858-2 are low power, RS485/RS422 transceivers operating on 5V supplies at maximum data rates of 20Mbps or 250kbps for low EMI. The receiver has a one-eighth unit load, supporting up to 256 nodes per bus (C, I-Grade), and a failsafe feature that guarantees a high output state under conditions of floating or shorted inputs.

The driver maintains a high output impedance over the entire common mode range when disabled or when the supply is removed. Excessive power dissipation caused by bus contention or a fault is prevented by current limiting all outputs and by thermal shutdown.

Enhanced ESD protection allows these parts to withstand ±15kV (human body model) on the transceiver interface pins without latchup or damage.

Features

20Mbps or Low EMI 250kbps Maximum Data Rate
No Damage or Latchup to ESD: ±15kV HBM
High Input Impedance Supports 256 Nodes (C, I-Grade)
Operation Up to 125°C (H-Grade)
Guaranteed Failsafe Receiver Operation Over the Entire Common Mode Range
Current Limited Drivers and Thermal Shutdown
Delayed Micropower Shutdown: 5µA Maximum (C, I-Grade)
Power Up/Down Glitch-Free Driver Outputs
Low Operating Current: 900µA Maximum in Receive Mode
Compatible with TIA/EIA-485-A Specifications
Available in 8-Lead and 10-Lead 3mm × 3mm DFN and 8-Lead and 10-Lead MSOP Packages

Typical Application

Applications

Low Power RS485/RS422 Transceiver
Level Translator
Backplane Transceiver

Packaging

**Order Information**
Part Number	Package	Temp	Price(1-99)	Price (1k)*
LTC2857CDD-1#PBF	3x3 DFN-8	C	$2.21	$1.55
LTC2857CDD-1#TRPBF	3x3 DFN-8	C		$1.61
LTC2857CDD-2#PBF	3x3 DFN-8	C	$2.21	$1.55
LTC2857CDD-2#TRPBF	3x3 DFN-8	C		$1.61
LTC2857CMS8-1#PBF	MS-8	C	$2.21	$1.55
LTC2857CMS8-1#TRPBF	MS-8	C		$1.61
LTC2857CMS8-2#PBF	MS-8	C	$2.21	$1.55
LTC2857CMS8-2#TRPBF	MS-8	C		$1.61
LTC2857HDD-1#PBF	3x3 DFN-8	H	$3.00	$2.05
LTC2857HDD-1#TRPBF	3x3 DFN-8	H		$2.11
LTC2857HDD-2#PBF	3x3 DFN-8	H	$3.00	$2.05
LTC2857HDD-2#TRPBF	3x3 DFN-8	H		$2.11
LTC2857HMS8-1#PBF	MS-8	H	$3.00	$2.05
LTC2857HMS8-1#TRPBF	MS-8	H		$2.11
LTC2857HMS8-2#PBF	MS-8	H	$3.00	$2.05
LTC2857HMS8-2#TRPBF	MS-8	H		$2.11
LTC2857IDD-1#PBF	3x3 DFN-8	I	$2.64	$1.86
LTC2857IDD-1#TRPBF	3x3 DFN-8	I		$1.92
LTC2857IDD-2#PBF	3x3 DFN-8	I	$2.64	$1.86
LTC2857IDD-2#TRPBF	3x3 DFN-8	I		$1.92
LTC2857IMS8-1#PBF	MS-8	I	$2.64	$1.86
LTC2857IMS8-1#TRPBF	MS-8	I		$1.92
LTC2857IMS8-2#PBF	MS-8	I	$2.64	$1.86
LTC2857IMS8-2#TRPBF	MS-8	I		$1.92