LTC4311
2
Low Voltage I C/SMBus
Accelerator
FEATURES DESCRIPTION
2
2
Improves I C Bus Rise Time Transition
The LTC 4311 is a dual I C active pull-up designed to
Ensures Data Integrity with Multiple Devices on the
enhance data transmission speed and reliability for bus
2
2
I C Bus.
loading conditions well beyond the 400pF I C speci 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 (<5A) 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
During positive bus transitions, the LTC4311 provides slew
8kV Human Body Model ESD Ruggedness
2
limited pull-up currents to quickly slew the I C or SMBus
2mm 2mm DFN and SC70 Packages
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 (<5A) 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 APPLICATION
2
Comparison of I C Waveforms for
the LTC4311 vs Resistor Pull-Up
V
V
CC
CC
LTC4311 2.5V
2.5V
V BUS1
CC
C1
ENABLE
0.01F 10k 10k
GND BUS2
2
I C 1V/DIV LTC4311
SCL
SDA
CLK DATA CLK DATA
IN IN IN IN
R = 15.8k
PULL-UP
CLK DATA CLK DATA
OUT OUT OUT OUT
4311 TA01b
V = 5V 1s/DIV
CC
C = 200pF
LD
DEVICE 1 DEVICE N
2
f = 100kHz
I C
4311 TA01a
4311fa
1LTC4311
ABSOLUTE MAXIMUM RATINGS
(Notes 1, 2)
Storage Temperature Range (DFN) ........65C to 125C
V to GND .................................................... 0.3 to 6V
CC
Storage Temperature Range (SC70).......65C to 125C
BUS1, BUS2, ENABLE Inputs ......................... 0.3 to 6V
Lead Temperature (Soldering 10, sec)
Operating Temperature
SC70 ............................................................ 300C
LTC4311C ................................................ 0C to 70C
LTC4311I..............................................40C to 85C
PIN CONFIGURATION
TOP VIEW
TOP VIEW
ENABLE 1 6 GND
V 1 6 BUS1
CC
NC 2 7 5 BUS2
GND 2 5 GND
V 3 4 BUS1
ENABLE 3 4 BUS2
CC
SC70 PACKAGE
DFN PACKAGE
6-LEAD PLASTIC SC70
6-LEAD (2mm s 2mm) PLASTIC DFN
T = 125C, = 150 C/W
JMAX JA
T = 125C, = 102C/W
JMAX JA
EXPOSED PAD (PIN 7) PCB CONNECTION TO GND IS OPTIONAL (Note 3)
ORDER INFORMATION
Lead Free Finish
TAPE AND REEL (MINI) TAPE AND REEL PART MARKING* PACKAGE DESCRIPTION TEMPERATURE RANGE
LTC4311CDC#TRMPBF LTC4311CDC#TRPBF LCNG 0C to 70C
6-Lead (2mm 2mm) Plastic DFN
LTC4311IDC#TRMPBF LTC4311IDC#TRPBF LCNG 40C to 85C
6-Lead (2mm 2mm) Plastic DFN
LTC4311CSC6#TRMPBF LTC4311CSC6#TRPBF LCNF 0C to 70C
6-Lead (2mm 2mm) Plastic SC70
LTC4311ISC6#TRMPBF LTC4311ISC6#TRPBF LCNF 40C to 85C
6-Lead (2mm 2mm) Plastic SC70
TRM = 500 pieces. *Temperature grades are identi ed by a label on the shipping container.
Consult LTC Marketing for parts speci ed with wider operating temperature ranges.
Consult LTC Marketing for information on lead based nish parts.
For more information on lead free part marking, go to: