LTC4311 Low Voltage I2C/SMBus Accelerator FEATURESDESCRIPTION ■ Improves I2C Bus Rise Time Transition The LTC®4311 is a dual I2C active pull-up designed to ■ Ensures Data Integrity with Multiple Devices on the enhance data transmission speed and reliability for bus I2C Bus. loading conditions well beyond the 400pF I2C specifi cation ■ Wide Supply Voltage Range: 1.6V to 5.5V limit. The LTC4311 operates at supply voltages from 1.6V ■ Improves Low State Noise Margin to 5.5V and is also compatible with SMBus. ■ Up to 400kHz Operation The LTC4311 allows multiple device connections or a lon- ■ Auto Detect Low Power Standby Mode ger, more capacitive interconnect, without compromising ■ Low (<5μA) Supply Current Shutdown slew rates or bus performance, by using two slew limited ■ Does Not Load Bus When Disabled or Powered Down pull-up currents. ■ Strong Slew Limited Pull-up Current ■ ±8kV Human Body Model ESD Ruggedness During positive bus transitions, the LTC4311 provides slew ■ 2mm × 2mm DFN and SC70 Packages limited pull-up currents to quickly slew the I2C or SMBus lines to the bus pull-up voltage. During negative transitions or steady DC levels, the currents are disabled to improve APPLICATIONS negative slew rate, and improve low state noise margins. ■ An auto detect standby mode reduces supply current if Notebook and Palmtop Computers ■ both SCL and SDA are high. When disabled, the LTC4311 Portable Instruments ■ goes into low (<5μA) current shutdown. Battery Chargers ■ Industrial Controls The LTC4311 is available in the 2mm × 2mm × 0.75mm ■ TV/Video Products DFN, and SC70 packages. ■ ACPI SMBus Interface , LT, LTC and LTM are registered trademarks of Linear Technology Corporation. All other trademarks are the property of their respective owners. Protected by U.S. Patents including 6356140 and 6650174. TYPICAL APPLICATIONComparison of I2C Waveforms forthe LTC4311 vs Resistor Pull-Up VCC VCC LTC4311 2.5V 2.5V VCC BUS1 C1 ENABLE 0.01μF 10k 10k GND BUS2 I2C 1V/DIV LTC4311 SCL SDA CLK DATA CLK DATA IN IN IN IN RPULL-UP = 15.8k CLK DATA CLK DATA OUT OUT OUT OUT 4311 TA01b VCC = 5V 1μs/DIV CLD = 200pF DEVICE 1 DEVICE N f 2 I C = 100kHz 4311 TA01a 4311fa 1