LTC6820 - isoSPI Isolated Communications Interface

Features

  • 1Mbps Isolated SPI Data Communications
  • Simple Galvanic Isolation Using Standard Transformers
  • Bidirectional Interface Over a Single Twisted Pair
  • Supports Cable Lengths Up to 100 Meters
  • Very Low EMI Susceptibility and Emissions
  • Configurable for High Noise Immunity or Low Power
  • Engineered for ISO26262 Compliant Systems
  • Requires No Software Changes in Most SPI Systems
  • Ultralow, 2μA Idle Current
  • Automatic Wake-Up Detection
  • Operating Temperature Range: –40°C to 125°C
  • 2.7V to 5.5V Power Supply
  • Interfaces to All Logic from 1.7V to 5.5V
  • Available in 16-Lead QFN and MSOP Packages
Designed for Automotive and Transportation Applications
AEC-Q100 data available for specific packages


Typical Application

LTC6820 Typical Application
LTC6820 Typical Application

Description

The LTC®6820 provides bidirectional SPI communications between two isolated devices through a single twisted pair connection. Each LTC6820 encodes logic states into signals that are transmitted across an isolation barrier to another LTC6820. The receiving LTC6820 decodes the transmission and drives the slave bus to the appropriate logic states. The isolation barrier can be bridged by a simple pulse transformer to achieve hundreds of volts of isolation.

The LTC6820 drives differential signals using matched source and sink currents, eliminating the requirement for a transformer center tap and reducing EMI. Precision window comparators in the receiver detect the differential signals. The drive currents and the comparator thresholds are set by a simple external resistor divider, allowing the system to be optimized for required cable lengths and desired signal-to-noise performance.

Packaging

For complete and up to date package information and drawings, please refer to our packaging page

Part Number Package Code Temp Package
Drawing
RoHS
LTC6820HMS#PBF MS-16 MS H 05-08-1669 Yes
LTC6820HMS#TRPBF MS-16 MS H 05-08-1669 Yes
LTC6820HUD#PBF 3x3 QFN-16 UD H 05-08-1700 Yes
LTC6820HUD#TRPBF 3x3 QFN-16 UD H 05-08-1700 Yes
LTC6820IMS#PBF MS-16 MS I 05-08-1669 Yes
LTC6820IMS#TRPBF MS-16 MS I 05-08-1669 Yes
LTC6820IUD#PBF 3x3 QFN-16 UD I 05-08-1700 Yes
LTC6820IUD#TRPBF 3x3 QFN-16 UD I 05-08-1700 Yes


LTC6820 Package Drawing
LTC6820 Package Drawing

Order Info

  • Part numbers ending in PBF are lead free. Solder plated terminal finish (SnPb) versions are non-standard and special terms and conditions and pricing applies if available. Please contact LTC marketing for information.
  • Part numbers containing TR or TRM are shipped in tape and reel or 500 unit mini tape and reel, respectively
  • Please refer to our general ordering information or the product datasheet for more details

Package Variations and Pricing

Part Number Package Temp Price
(1-99)
Price
(1k)*
RoHS
LTC6820HMS#PBF MS-16 H $3.58 $2.57 Yes
LTC6820HMS#TRPBF MS-16 H $2.63 Yes
LTC6820HUD#PBF 3x3 QFN-16 H $3.58 $2.57 Yes
LTC6820HUD#TRPBF 3x3 QFN-16 H $2.63 Yes
LTC6820IMS#PBF MS-16 I $3.20 $2.29 Yes
LTC6820IMS#TRPBF MS-16 I $2.35 Yes
LTC6820IUD#PBF 3x3 QFN-16 I $3.20 $2.29 Yes
LTC6820IUD#TRPBF 3x3 QFN-16 I $2.35 Yes
Buy NowRequest Samples
* The USA list pricing shown is for BUDGETARY USE ONLY, shown in United States dollars (FOB USA per unit for the stated volume), and is subject to change. International prices may differ due to local duties, taxes, fees and exchange rates. For volume-specific price or delivery quotes, please contact your local Linear Technology sales office or authorized distributor.

Demo Boards

Linear Technology offers many demo boards free of charge to qualified customers. Contact your local sales office or distributor to inquire about a demo board. Certain demo boards are also available for sale via credit card on this website. Demo boards are for evaluation purposes only. It remains the customer’s responsibility to verify proper and reliable operation in the actual end application.

Part Number Description Price Documentation
DC1907A LTC6820 isoSPI 2-Wire Serial Analyzer $150.00
DC1941D LTC6820 isoSPI Demoboard (DC590B required) $75.00
DC2100B-C 12 Cell 4A Controller Board. Bi-Directional Active Cell Balancer with LTC3300-1, LTC6804-2 & LTC6820 $475.00
Buy Now
Click here to view our complete list of demo boards

Designed for Automotive and Transportation Applications

AEC-Q100 data is available for these specific part numbers. Please contact your local sales representative for more information regarding reliability reports or to inquire about parts that are not included. For more information, view our Automotive and Transportation page

Part Number Package Temp Price
(1-99)
Price
(1k)*
RoHS
LTC6820HMS#PBF MS-16 H $3.58 $2.57 Yes
LTC6820HMS#TRPBF MS-16 H $2.63 Yes
LTC6820HUD#PBF 3x3 QFN-16 H $3.58 $2.57 Yes
LTC6820HUD#TRPBF 3x3 QFN-16 H $2.63 Yes
LTC6820IMS#PBF MS-16 I $3.20 $2.29 Yes
LTC6820IMS#TRPBF MS-16 I $2.35 Yes
LTC6820IUD#PBF 3x3 QFN-16 I $3.20 $2.29 Yes
LTC6820IUD#TRPBF 3x3 QFN-16 I $2.35 Yes
Buy NowRequest Samples
* The USA list pricing shown is for BUDGETARY USE ONLY, shown in United States dollars (FOB USA per unit for the stated volume), and is subject to change. International prices may differ due to local duties, taxes, fees and exchange rates. For volume-specific price or delivery quotes, please contact your local Linear Technology sales office or authorized distributor.

Applications

  • Industrial Networking
  • Battery Monitoring Systems
  • Remote Sensors

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Design Tools

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