LTC4312 Pin-Selectable, 2-Channel, 2-Wire Multiplexer with Bus Buffers FEATURES DESCRIPTION n 1:2 Multiplexer/Switch for 2-Wire Bus The LTC 4312 is a hot-swappable 2-channel 2-wire bus n Bidirectional Buffer for SDA and SCL Lines multiplexer that allows one upstream bus to connect to n any combination of downstream busses or channels. High Noise Margin with V = 0.3V IL CC n An individual enable pin controls each connection. The ENABLE Pins Connect SDA and SCL Lines n LTC4312 provides bidirectional buffering, keeping the up- Selectable Rise Time Accelerator Current and stream bus capacitance isolated from the downstream bus Activation Voltage n capacitances. The high noise margin allows the LTC4312 Level Shift 1.5V, 1.8V, 2.5V, 3.3V and 5V Busses 2 n to be interoperable with I C devices that drive a high V Prevents SDA and SCL Corruption During Live Board OL (> 0.4V). The LTC4312 supports level translation between Insertion and Removal from Backplane n 1.5V, 1.8V, 2.5V, 3.3V and 5V busses. The hot-swappable Stuck Bus Disconnect and Recovery 2 2 nature of the LTC4312 allows I/O card insertion into, and n Compatible with I C, I C Fast Mode and SMBus removal from, a live backplane without corruption of the n 4kV Human Body Model (HBM) ESD Ruggedness data and clock busses. n 14-Lead 4mm 3mm DFN and 16-Lead MSOP Packages If both data and clock are not simultaneously high at least once in 45ms and DISCEN is high, a FAULT signal is APPLICATIONS generated indicating a stuck bus low condition, the input is disconnected from each enabled output channel and up n Telecommunications Systems Including ATCA to 16 clocks are generated on the enabled downstream n Address Expansion busses. A three state ACC pin enables input and output n Level Translator side rise time accelerators of varying strengths and sets n Capacitance Buffers/Bus Extender the V voltage. IL,RISING n Live Board Insertion L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks of Linear n PMBus Technology Corporation. Hot Swap is a trademark of Linear Technology Corporation. All other trademarks are the property of their respective owners. Protected by U.S. Patents, including 6356140, 6650174, 7032051, 7478286. TYPICAL APPLICATION 3.3V 3.3V Rising Edge from Asserted Low with Level Translation 0.01F 0.01F 10k 10k V V 10k 10k CC CC2 6V C + C = 100pF SCLOUT1 SCLOUT2 C = 50pF SCLIN SCLIN SCLIN SCLOUT2 5V SDAIN SDAIN ENABLE1 ENABLE1 SCLOUT1 SCLOUT1 ENABLE2 ENABLE2 SDAOUT1 SDAOUT1 SCLOUT1 3.3V 5V 3.3V SCLIN LTC4312 10k 10k 10k ACC SCLOUT2 SCLOUT2 DISCEN SDAOUT2 SDAOUT2 0V FAULT FAULT GND 200ns/DIV 4312 TA01b 4314 TA01a 4312f 1 1V/DIVLTC4312 ABSOLUTE MAXIMUM RATINGS (Notes 1, 2) Supply Voltage Output DC Sink Currents V , V ................................................. 0.3V to 6V FAULT ................................................................. 50mA CC CC2 Input Voltages Operating Ambient Temperature Range ACC, DISCEN, ENABLE1-2 ....................... 0.3V to 6V LTC4312C ................................................ 0C to 70C Input/Output Voltages LTC4312I..............................................40C to 85C SDAIN, SCLIN, SCLOUT1-2, Storage Temperature Range ..................65C to 150C SDAOUT1-2, FAULT ................................. 0.3V to 6V Lead Temperature (Soldering, 10 sec) MSOP .............................................................. 300C PIN CONFIGURATION TOP VIEW TOP VIEW V 1 14 DISCEN CC DISCEN 1 16 ACC 2 13 SCLOUT1 ACC V 2 15 GND CC 3 12 SDAOUT1 GND SCLOUT1 3 14 NC SDAOUT1 4 13 NC SDAIN 4 15 11 V CC2 SDAIN 5 12 V CC2 SCLIN 5 10 FAULT SCLIN 6 11 FAULT SCLOUT2 6 9 ENABLE1 SCLOUT2 7 10 ENABLE1 SDAOUT2 7 8 ENABLE2 SDAOUT2 8 9 ENABLE2 MS PACKAGE 16-LEAD PLASTIC MSOP DE14 PACKAGE 14-LEAD (4mm = 3mm) PLASTIC DFN T = 150C, = 120C/W, = 21C/W JMAX JA JC T = 125C, = 43C/W, = 5C/W JMAX JA JC EXPOSED PAD (PIN 15) PCB CONNECTION TO GND IS OPTIONAL ORDER INFORMATION LEAD FREE FINISH TAPE AND REEL PART MARKING* PACKAGE DESCRIPTION TEMPERATURE RANGE LTC4312IDE PBF LTC4312IDE TRPBF 4312 14-Lead (4mm 3mm) DFN 40C to 85C LTC4312IMS PBF LTC4312IMS TRPBF 4312 16-Lead Plastic MSOP 40C to 85C LTC4312CDE PBF LTC4312CDE TRPBF 4312 14-Lead (4mm 3mm) DFN 0C to 70C LTC4312CMS PBF LTC4312CMS TRPBF 4312 16-Lead Plastic MSOP 0C to 70C Consult LTC Marketing for parts speci ed with wider operating temperature ranges. *The temperature grade is identi ed by a label on the shipping container. Consult LTC Marketing for information on non-standard lead based nish parts. For more information on lead free part marking, go to: