Up to 8.0Gbps Dual Passive Switches MAX4888B/MAX4888C
10Pages

________________________________________________________________ Maxim Integrated Products 1 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. MAX4888B/MAX4888C Up to 8.0Gbps Dual Passive Switches 19-5706; Rev 0; 12/10 Typical Operating Circuit General Description The MAX4888B/MAX4888C dual double-pole/doublethrow (2 x DPDT), high-speed passive switches are ideal for switching two half-lanes of PCI ExpressM (PCIe) data between two possible destinations. These devices feature a dual digital control input to switch signal paths. The MAX4888C is intended for use in systems where both the input and output are capacitively coupled (e.g., SAS, SATA, XAUI, and PCIe) and provides a 10FA (typ) source current and a 60kI (typ) internal biasing resistor to GND at the AOUT_ and BOUT_ pins. The devices are fully specified to operate from a single +3.3V (typ) power supply. Both devices are available in an industry-standard 3.5mm x 5.5mm, 28-pin TQFN package. They operate over the -40NC to +85NC extended temperature range. Applications Desktop PCs Notebook PCs Servers Features S Single +3.3V Power-Supply Voltage S Supports PCIe Gen I, Gen II, and Gen III Data Rates S Supports Up To and Including 6.0Gbps SAS/SATA Signals S Supports Other High-Speed Interfaces (e.g., XAUI) S Superior Bandwidth Return Loss S Small, 3.5mm x 5.5mm, 28-Pin TQFN Package Ordering Information +Denotes a lead(Pb)-free/RoHS-compliant package. *EP = Exposed pad. PCI Express is a registered trademark of PCI-SIG Corp. MAX4888C VCC GND CONNECTION SELECT AOUTA+ MAX4888C VCC GND AOUTABOUTA+ SEL SELB SEL SELB PCIe HOST BOUTAAIN+ AINBIN+ BINAIN+ AINBIN+ AOUTB+ BINAOUTBBOUTB+ SAS HOST NOTE: CAPACITIVE COUPLING WAS OMITTED TO SIMPLIFY ILLUSTRATION. PCIe DEVICE SAS DEVICE BOUTBAOUTA+ AOUTABOUTA+ BOUTAAOUTB+ AOUTBBOUTB+ BOUTBPART TEMP RANGE PIN-PACKAGE MAX4888BETI+ -40NC to +85NC 28 TQFN-EP* MAX4888CETI+ -40NC to +85NC 28 TQFN-EP*

MAX4888B/MAX4888C Up to 8.0Gbps Dual Passive Switches 3 ELECTRICAL CHARACTERISTICS (continued) (VCC = 3.3V Q10%, TA = -40NC to +85NC, unless otherwise noted. Typical values are at VCC = 3.3V, TA = +25NC, unless otherwise noted.) (Note 3) Note 3: All units are 100% production tested at TA = +85NC. Limits over the operating temperature range are guaranteed by design and characterization and are not production tested. Note 4: DRON = RON(MAX) - RON(MIN). Note 5: Flatness is defined as the difference between the maximum and minimum value of on-resistance as measured over the specified...

MAX4888B/MAX4888C Up to 8.0Gbps Dual Passive Switches 4 Test Circuits/Timing Diagrams Figure 1. Switching Time Table 1. Insertion Loss Mask LOAD SOURCEVOUTZLSELZS10%90%50%50%tON_SELtOFF_SELVOUTSELTHE FREQUENCY OF THE SIGNAL SHOULD BE ABOVE THE HIGHPASS FILTER CORNER OF THE COUPLING CAPACITORS.MAX4888BMAX4888C FREQUENCY RANGE (GHz) MAXIMUM INSERTION LOSS (dB) 0 to 2.5 1/3 x fGHZ + 17/30 2.5 to 5 2/5 x fGHZ - 2/5 5 to 8 18/5 x fGHZ - 4/15 Greater than 8 2 x fGHZ - 12

MAX4888B/MAX4888C Up to 8.0Gbps Dual Passive Switches 5 Test Circuits/Timing Diagrams (continued) Figure 2. Propagation Delay and Output Skew LOA DSOURCEVOUTpZLVOUTnZLSELCALIBRATIONTRACESVS+ZSVS-ZSVCALpZLVCALnZLVSC+ZSVSC-ZS50%50%VCM50%50%VCMVCMVCMtPDrtPDftSK1tSK2VOUTnAFTER ELIMINATING SOURCE AND CABLE SKEWS.VOUTptPD = max (tPDr, tPDf)tSKEW = max (tSK1, tSK2)VOUTp - VOUTnVCALp - VCALnMAX4888BMAX4888C

MAX4888B/MAX4888C Up to 8.0Gbps Dual Passive Switches 7 Pin Configuration Pin Description TOP VIEW TQFN11121314GNDVCCGNDVCC28+272625GNDVCCGNDVCC1234567891024232221201918171615GNDBOUTB-BOUTB+BIN-BIN+AOUTB-AOUTB+AIN-AIN+GNDSELBGNDBOUTA-BOUTA+VCCGNDAOUTA-AOUTA+GNDSEL*EP*CONNECT EXPOSED PAD TO GND.MAX4888BMAX4888C PIN NAME FUNCTION 1, 10, 11, 13, 16, 20, 23, 26, 28 GND Ground 2 AIN+ Analog Switch 1, Common Positive Terminal 3 AIN- Analog Switch 1, Common Negative Terminal 4 AOUTB+ Analog Switch 1, Normally Open Positive Terminal 5 AOUTB- Analog Switch 1, Normally Open Negative Terminal 6 BIN+...

MAX4888B/MAX4888C Up to 8.0Gbps Dual Passive Switches 8 Functional Diagram/Truth Table MAX4888C AOUTA+AIN+AOUTA-AIN-AOUTB+AOUTB-BOUTA+BIN+BOUTA-BIN-SELBVCCVCCBOUTB+BOUTB-GNDSELCONTROLMAX4888BAOUTA+AIN+AOUTA-AIN-AOUTB+AOUTB-BOUTA+BIN+BOUTA-BIN-SELBVCCVCCBOUTB+BOUTB-GNDSELCONTROL0 (DEFAULT)10 (DEFAULT)1SEL001 (DEFAULT)1 (DEFAULT)SELBOFFOFFONOFFAIN_, BIN_TO AOUTA_,BOUTA_ONONOFFONAIN_, BIN_TO AOUTB_,BOUTB_

MAX4888B/MAX4888C Up to 8.0Gbps Dual Passive Switches 9 Detailed Description The MAX4888B high-speed passive switch routes high-speed differential signals such as PCIe, SAS, SATA, and XAUI from one source to two possible destinations or vice versa. The MAX4888B is ideal for routing PCIe signals to change the system configuration. The MAX4888C features a 10FA (typ) source current and a 60kI (typ) internal biasing resistor to GND at the AOUTA_, BOUTA_, AOUTB_, and BOUTB_ terminals. The MAX4888C is ideal for circuits that are capacitively coupled at both the output and input. These devices are...

Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are implied. Maxim reserves the right to change the circuitry and specifications without notice at any time. 10 Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 © 2010 Maxim Integrated Products Maxim is a registered trademark of Maxim Integrated Products, Inc. MAX4888B/MAX4888C Up to 8.0Gbps Dual Passive Switches Revision History REVISION NUMBER REVISION DATE DESCRIPTION PAGES CHANGED 0 12/10 Initial release —