DS3205 Datasheet, PDF (1/20 Pages) Maxim Integrated Products – Hot-Swappable Bus Buffer for I2C, SMBus, IPMI, and ATCA

Rev: 111607
DS3205
Hot-Swappable Bus Buffer for
I²C, SMBus, IPMI, and ATCA
General Description
The DS3205 bus buffer enables hot insertion and
extraction of boards without corruption of the
backplane’s 2-wire bus (I²C, SMBus™, IPMI, etc.).
When a board is inserted, the DS3205 presents high-
impedance SCL and SDA connections to the
backplane until V_DD rises above 2.5V. During normal
operation, the DS3205 provides bidirectional
buffering to keep backplane and board capacitances
isolated.
Rise-time accelerators on each 2-wire bus pin enable
the use of lower current pullup resistors while still
meeting rise-time requirements.
Applications
Hot-Swappable Boards for AdvancedTCA^®,
CompactPCI^®, VME, and Other Backplanes in
Chassis-Oriented Telecom, Datacom,
Computing, and Storage Systems
Capacitance Buffer
Bus Extender
Fault Isolator
Ordering Information
PART
DS3205DN+
TEMP RANGE
PIN-
PACKAGE
-40°C to +85°C 14 TDFN
PKG
CODE
T1433-1
+Denotes a lead-free package.
Features
♦ Compliant to PICMG 3.0 IPMI I²C Requirements
♦ Bidirectional Buffer for SCL and SDA Lines
♦ Compatible with I²C, I²C Fast Mode, SMBus,
IPMI, and ATCA^® Standards (Up to 400kHz)
♦ Prevents Corruption of System SCL and SDA
Lines During Live Insertion/Removal of Boards
♦ Increases Fanout by Connecting Board Bus to
Backplane Bus with < 10pF Additional Load
♦ Automatically Delays Initial Bus Connection
Until Both Bus Segments Are Idle
♦ SCL and SDA Pins High-Z When V_DD = 0V
♦ 1V Precharge on SCL and SDA Lines
♦ ENABLE Input Pin Connects or Isolates Buses
♦ READY Output Pin Indicates “Connected”
♦ FAULT Output Pin Indicates “Stuck Bus”
♦ Optional Rise-Time Accelerators on All Bus
Pins
♦ Configurable Rise-Time Accelerator Slew Rate
Threshold (0.8V/μs or 1.25V/μs)
♦ Supports Clock Stretching and Multiple Bus
Master Arbitration and Synchronization
♦ Optionally Disconnects Board from Backplane
When Bus is Stuck Low for ≥ 30ms
♦ Optionally Attempts to Recover a Stuck Bus by
Clocking Board SCL
♦ ±15kV ESD Protection (Human Body Model) on
Bus Pins
♦ Wide Operating Voltage Range: 2.7V to 5.5V
♦ 5V Tolerant I/Os
♦ Tiny 14-Pin, 3mm x 3mm TDFN Package
SMBus is a trademark of Intel Corp.
ATCA, AdvancedTCA, and CompactPCI are registered trademarks of PCI Industrial Computer Manufacturers Group (PICMG).
Maxim Integrated Products 1
Some revisions of this device may incorporate deviations from published specifications known as errata. Multiple revisions of
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www.maxim-ic.com/errata. For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642, or
visit Maxim’s website at www.maxim-ic.com.