LTC4313 - 2-Wire Bus Buffers with High Noise Margin


  • Bidirectional Buffer Increases Fanout
  • High Noise Margin with VIL = 0.3•VCC
  • Compatible with Non-Compliant I2C Devices That Drive a High VOL
  • Strong (LTC4313-1) and 2.5mA (LTC4313-2) Rise Time Accelerator Current
  • Level Shift 1.5V, 1.8V, 2.5V, 3.3V and 5V Busses
  • Prevents SDA and SCL Corruption During Live Board Insertion and Removal from Backplane
  • Stuck Bus Disconnect and Recovery
  • Compatible with I2C, I2C Fast Mode and SMBus
  • ±4kV Human Body Model ESD Ruggedness
  • High Impedance SDA, SCL Pins When Unpowered
  • 8-Lead MSOP and 8-Lead (3mm × 3mm) DFN Packages

Typical Application

LTC4313 Typical Application
LTC4313 Typical Application


The LTC®4313 is a hot swappable 2-wire bus buffer that provides bidirectional buffering while maintaining a low offset voltage and high noise margin up to 0.3 • VCC. The high noise margin allows the LTC4313 to be interoperable with devices that drive a high VOL (>0.4V) and allows multiple LTC4313s to be cascaded. The LTC4313-1 and LTC4313-2 support level translation between 3.3V and 5V busses. In addition to these voltages, the LTC4313-3 also supports level translation to 1.5V, 1.8V and 2.5V.

During insertion, the SDA and SCL lines are pre-charged to 1V to minimize bus disturbances. Connection is established between the input and output after ENABLE is asserted high and a stop bit or bus idle condition has been detected on the SDA and SCL pins.

If both data and clock are not simultaneously high at least once in 45ms, the input is disconnected from the output. Up to 16 clock pulses are subsequently generated to free the stuck bus. Rise time accelerators (RTAs) provide pull-up currents on SDA and SCL rising edges to meet rise time specifications in heavily loaded systems. The RTAs are configured as slew limited switches in the LTC4313-1 and 2.5mA current sources in the LTC4313-2. The LTC4313-3 does not have RTAs.


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
LTC4313CDD-1#PBF 3x3 DFN-8 DD C 05-08-1698 Yes
LTC4313CDD-1#TRPBF 3x3 DFN-8 DD C 05-08-1698 Yes
LTC4313CDD-2#PBF 3x3 DFN-8 DD C 05-08-1698 Yes
LTC4313CDD-2#TRPBF 3x3 DFN-8 DD C 05-08-1698 Yes
LTC4313CDD-3#PBF 3x3 DFN-8 DD C 05-08-1698 Yes
LTC4313CDD-3#TRPBF 3x3 DFN-8 DD C 05-08-1698 Yes
LTC4313CMS8-1#PBF MS-8 MS8 C 05-08-1660 Yes
LTC4313CMS8-1#TRPBF MS-8 MS8 C 05-08-1660 Yes
LTC4313CMS8-2#PBF MS-8 MS8 C 05-08-1660 Yes
LTC4313CMS8-2#TRPBF MS-8 MS8 C 05-08-1660 Yes
LTC4313CMS8-3#PBF MS-8 MS8 C 05-08-1660 Yes
LTC4313CMS8-3#TRPBF MS-8 MS8 C 05-08-1660 Yes
LTC4313IDD-1#PBF 3x3 DFN-8 DD I 05-08-1698 Yes
LTC4313IDD-1#TRPBF 3x3 DFN-8 DD I 05-08-1698 Yes
LTC4313IDD-2#PBF 3x3 DFN-8 DD I 05-08-1698 Yes
LTC4313IDD-2#TRPBF 3x3 DFN-8 DD I 05-08-1698 Yes
LTC4313IDD-3#PBF 3x3 DFN-8 DD I 05-08-1698 Yes
LTC4313IDD-3#TRPBF 3x3 DFN-8 DD I 05-08-1698 Yes
LTC4313IMS8-1#PBF MS-8 MS8 I 05-08-1660 Yes
LTC4313IMS8-1#TRPBF MS-8 MS8 I 05-08-1660 Yes
LTC4313IMS8-2#PBF MS-8 MS8 I 05-08-1660 Yes
LTC4313IMS8-2#TRPBF MS-8 MS8 I 05-08-1660 Yes
LTC4313IMS8-3#PBF MS-8 MS8 I 05-08-1660 Yes
LTC4313IMS8-3#TRPBF MS-8 MS8 I 05-08-1660 Yes

LTC4313 Package Drawing
LTC4313 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
LTC4313CDD-1#PBF 3x3 DFN-8 C $3.43 $2.40 Yes
LTC4313CDD-1#TRPBF 3x3 DFN-8 C $2.46 Yes
LTC4313CDD-2#PBF 3x3 DFN-8 C $3.43 $2.40 Yes
LTC4313CDD-2#TRPBF 3x3 DFN-8 C $2.46 Yes
LTC4313CDD-3#PBF 3x3 DFN-8 C $3.43 $2.40 Yes
LTC4313CDD-3#TRPBF 3x3 DFN-8 C $2.46 Yes
LTC4313CMS8-1#PBF MS-8 C $3.43 $2.40 Yes
LTC4313CMS8-1#TRPBF MS-8 C $2.46 Yes
LTC4313CMS8-2#PBF MS-8 C $3.43 $2.40 Yes
LTC4313CMS8-2#TRPBF MS-8 C $2.46 Yes
LTC4313CMS8-3#PBF MS-8 C $3.43 $2.40 Yes
LTC4313CMS8-3#TRPBF MS-8 C $2.46 Yes
LTC4313IDD-1#PBF 3x3 DFN-8 I $3.94 $2.76 Yes
LTC4313IDD-1#TRPBF 3x3 DFN-8 I $2.82 Yes
LTC4313IDD-2#PBF 3x3 DFN-8 I $3.94 $2.76 Yes
LTC4313IDD-2#TRPBF 3x3 DFN-8 I $2.82 Yes
LTC4313IDD-3#PBF 3x3 DFN-8 I $3.94 $2.76 Yes
LTC4313IDD-3#TRPBF 3x3 DFN-8 I $2.82 Yes
LTC4313IMS8-1#PBF MS-8 I $3.94 $2.76 Yes
LTC4313IMS8-1#TRPBF MS-8 I $2.82 Yes
LTC4313IMS8-2#PBF MS-8 I $3.94 $2.76 Yes
LTC4313IMS8-2#TRPBF MS-8 I $2.82 Yes
LTC4313IMS8-3#PBF MS-8 I $3.94 $2.76 Yes
LTC4313IMS8-3#TRPBF MS-8 I $2.82 Yes
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* 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.

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  • Capacitance Buffers/Bus Extender
  • Live Board Insertion
  • Telecommunications Systems Including ATCA
  • Level Translation
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