LTC4302 - Addressable 2-Wire Bus Buffer

Features

  • Bidirectional Buffer for SDA and SCL Lines Increases Fanout
  • Connect SDA and SCL Lines with 2-Wire Bus Commands
  • Prevents SDA and SCL Corruption During Live Board Insertion and Removal from Backplane
  • Compatible with I²C™ Standard Mode, I²C Fast Mode and SMBus Standards
  • Rise Time Accelerators on SDA, SCL Lines
  • 1V Precharge on SDA and SCL Lines
  • 32 Unique Addresses from a Single ADDRESS Pin
  • Two General Purpose Inputs-Outputs (LTC4302-1)
  • Translates Between 5V and 3.3V Systems (LTC4302-2)
  • Small 10-Pin MSOP Package
Designed for Automotive and Transportation Applications
AEC-Q100 data available for specific packages


Typical Application

LTC4302 Typical Application
LTC4302 Typical Application

Description

The LTC4302-1/LTC4302-2 addressable I²C bus and SMBus compatible bus buffers allow a peripheral board to be inserted and removed from a live backplane without corruption of the bus. The LTC4302-1/LTC4302-2 maintain electrical isolation between the backplane and peripheral board until their VCC supply is valid and a master device on the backplane side addresses the LTC4302-1/ LTC4302-2 and commands them to connect. The LTC4302-1/LTC4302-2’s ADDRESS pin provides 32 possible addresses set by an external resistive divider between VCC and GND. The LTC4302-1/LTC4302-2 work with supply voltages ranging from 2.7V to 5.5V. The SDA and SCL inputs and outputs do not load the bus lines when VCC is low.

Rise time accelerator circuitry* allows for heavier capacitive bus loading while still meeting system timing requirements. During insertion, the SDA and SCL lines are precharged to 1V to minimize bus disturbances. Two general purpose input/output pins (GPIOs) on the LTC4302-1 can be configured as inputs, open-drain outputs or push-pull outputs. The LTC4302-2 option replaces one GPIO pin with a second supply voltage pin VCC2, providing level shifting between systems with different supply voltages. The LTC4302-1/LTC4302-2 are available in a 10-pin MSOP package.

*U.S. Patent No. 6,650,174

Packaging

CAD Symbols and Footprints: The downloadable Zip file below contains the schematic symbol and PCB footprints.

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

Part Number Package Code Temp Package
Drawing
RoHS
LTC4302CMS-1#PBF MS-10 MS C 05-08-1661 Yes
LTC4302CMS-1#TRPBF MS-10 MS C 05-08-1661 Yes
LTC4302CMS-2#PBF MS-10 MS C 05-08-1661 Yes
LTC4302CMS-2#TRPBF MS-10 MS C 05-08-1661 Yes
LTC4302IMS-1#PBF MS-10 MS I 05-08-1661 Yes
LTC4302IMS-1#TRPBF MS-10 MS I 05-08-1661 Yes
LTC4302IMS-2#PBF MS-10 MS I 05-08-1661 Yes
LTC4302IMS-2#TRPBF MS-10 MS I 05-08-1661 Yes


LTC4302 Package Drawing
LTC4302 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
LTC4302CMS-1#PBF MS-10 C $2.90 $2.50 Yes
LTC4302CMS-1#TRPBF MS-10 C $2.56 Yes
LTC4302CMS-2#PBF MS-10 C $2.90 $2.50 Yes
LTC4302CMS-2#TRPBF MS-10 C $2.56 Yes
LTC4302IMS-1#PBF MS-10 I $3.35 $2.90 Yes
LTC4302IMS-1#TRPBF MS-10 I $2.96 Yes
LTC4302IMS-2#PBF MS-10 I $3.35 $2.90 Yes
LTC4302IMS-2#TRPBF MS-10 I $2.96 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
DC757A-A LTC4302CMS-1 | Addressable 2-Wire Bus Buffer (req DC590) $50.00
DC757A-B LTC4302CMS-2 | Addressable 2-Wire Bus Buffer with Supply Level Shifting (req DC590) $50.00
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Companion Boards

Part Number Description Price Documentation
DC590B Isolated USB Serial Controller for Linear Technology QuikEval-Compatible Demo Boards $50.00
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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
LTC4302IMS-1#PBF MS-10 I $3.35 $2.90 Yes
LTC4302IMS-1#TRPBF MS-10 I $2.96 Yes
LTC4302IMS-2#PBF MS-10 I $3.35 $2.90 Yes
LTC4302IMS-2#TRPBF MS-10 I $2.96 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

  • Live Board Insertion
  • 5V/3.3V Level Translator
  • Servers
  • Capacitance Buffer/Bus Extender
  • Nested Addressing

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Design Tools

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