LTC4303 - Hot Swappable 2-Wire Bus Buffer with Stuck Bus Recovery

Features

  • Automatic Disconnect of SDA/SCL Lines when Bus is Stuck Low for ≥ 30ms
  • Recovers Stuck Busses with Automatic Clocking*
  • Bidirectional Buffer* for SDA and SCL Lines Increases Fanout
  • Prevents SDA and SCL Corruption During Live Board Insertion and Removal from Backplane
  • Pin Compatible with LTC4300A-1
  • ±15kV Human Body Model ESD Protection
  • Isolates Input SDA and SCL Lines from Output
  • Compatible with I2CTM, I2C Fast-Mode and SMBus Standards (Up to 400kHz Operation)
  • READY Open Drain Output
  • 1V Precharge on All SDA and SCL Lines
  • High Impedance SDA, SCL Pins for VCC = 0V
  • ENABLE Gates Connection from Input to Output
  • MSOP 8-Pin and DFN (3mm × 3mm) Packages
Designed for Automotive and Transportation Applications
AEC-Q100 data available for specific packages


Typical Application

LTC4303 Typical Application
LTC4303 Typical Application

Description

The LTC4303 hot swappable 2-wire Bus Buffer allows I/O card insertion into a live backplane without corruption of the data and clock busses. When a connection is made, the LTC4303 provides bidirectional buffering, keeping the backplane and card capacitances isolated. If SDAOUT or SCLOUT is low for ≥ 30ms (typ), the LTC4303 automatically breaks the data and clock bus connection. At this time the LTC4303 automatically generates up to 16 clock pulses on SCLOUT in an attempt to free the bus. A connection will be enabled automatically when the bus becomes free.

Rise-time accelerator circuitry allows the use of larger pull-up resistors while still meeting rise-time requirements. During insertion, the SDA and SCL lines are precharged to 1V to minimize bus disturbances. When driven high, ENABLE allows the LTC4303 to connect after a stop bit or bus idle occurs. Driving ENABLE low breaks the connection between SDAIN and SDAOUT, SCLIN and SCLOUT. READY is an open drain output that indicates when the backplane and card sides are connected together.

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
LTC4303CDD#PBF 3x3 DFN-8 DD C 05-08-1698 Yes
LTC4303CDD#TRPBF 3x3 DFN-8 DD C 05-08-1698 Yes
LTC4303CMS8#PBF MS-8 MS8 C 05-08-1660 Yes
LTC4303CMS8#TRPBF MS-8 MS8 C 05-08-1660 Yes
LTC4303IDD#PBF 3x3 DFN-8 DD I 05-08-1698 Yes
LTC4303IDD#TRPBF 3x3 DFN-8 DD I 05-08-1698 Yes
LTC4303IMS8#PBF MS-8 MS8 I 05-08-1660 Yes
LTC4303IMS8#TRPBF MS-8 MS8 I 05-08-1660 Yes


LTC4303 Package Drawing
LTC4303 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
LTC4303CDD#PBF 3x3 DFN-8 C $3.07 $2.15 Yes
LTC4303CDD#TRPBF 3x3 DFN-8 C $2.21 Yes
LTC4303CMS8#PBF MS-8 C $3.00 $2.10 Yes
LTC4303CMS8#TRPBF MS-8 C $2.16 Yes
LTC4303IDD#PBF 3x3 DFN-8 I $3.70 $2.58 Yes
LTC4303IDD#TRPBF 3x3 DFN-8 I $2.64 Yes
LTC4303IMS8#PBF MS-8 I $3.61 $2.52 Yes
LTC4303IMS8#TRPBF MS-8 I $2.58 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.

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
LTC4303IMS8#PBF MS-8 I $3.61 $2.52 Yes
LTC4303IMS8#TRPBF MS-8 I $2.58 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

  • Hot Board Insertion
  • Servers
  • Capacitance Buffer/Bus Extender
  • RAID Systems

Product Notifications

Please login to your MyLinear account for notifications of datasheet updates, new document releases and LTspice model announcements for your favorite products. If you do not have a MyLinear account you may Sign Up Now.

Forgot your password? Click here.
Need help? Email mylinear@linear.com with questions and comments.

Design Tools

Linear Technology provides a variety of custom design simulation tools and device models to allow even novice designers to quickly and easily evaluate circuits using high performance switching regulators, amplifiers, data converters, filters and more. Please visit our Design Tools page to view and download:

  • LTspice - A powerful SPICE simulator, schematic capture and waveform viewer with enhancements and models for easing the simulation of switching regulators
  • LTpowerCAD - A complete power supply selection, synthesis and design tool
  • LTpowerPlay - A development environment supporting Linear Technology's Digital Power System Management (PSM) products
  • PScope & QuikEval - USB-based product demonstration and data acquisition system for use with our ADCs, DACs, and more
  • Linduino - Arduino compatible system for developing and distributing firmware libraries and example code
  • LinearLab Tools - A collection of Matlab and Python programs that provide direct access to Linear Technology’s data converter evaluation boards
  • And More!

Technical Support