Summary of the content on the page No. 1
MAX4888A/MAX4889A
19-0770; Rev 0; 4/07
5.0Gbps PCI Express Passive Switches
General Description Features
The MAX4888A/MAX4889A high-speed passive switches
Single 1.65V to 3.6V Power-Supply Voltage
®
route PCI Express (PCIe) data between two possible
Low Same-Pair Skew of 7ps
destinations. The MAX4888A is a quad single-pole/dou-
ble-throw (4 x SPDT) switch ideally suited for switching
Low 120µA (Max) Quiescent Current
two half lanes of PCIe data between two destinations. The
Supports PCIe
Summary of the content on the page No. 2
5.0Gbps PCI Express Passive Switches ABSOLUTE MAXIMUM RATINGS (All voltages referenced to GND, unless otherwise noted.) Continuous Power Dissipation (T = +70°C) A V+.............................................................................-0.3V to +4V 28-Pin TQFN (derate 20.8mW/°C above +70°C) ....1666.7mW SEL, COM__, NO__, NC__ (Note 1) .............-0.3V to (V+ + 0.3V) 42-Pin TQFN (derate 35.7mW/°C above +70°C) ....2857.1mW | COM__ - NO__ |, | COM__ - NC__ | (Note 1)...................0 to
Summary of the content on the page No. 3
MAX4888A/MAX4889A 5.0Gbps PCI Express Passive Switches ELECTRICAL CHARACTERISTICS (continued) (V+ = 3.0V to 3.6V, T = -40°C to +85°C, unless otherwise noted. Typical values are at V+ = 3.3V, T = +25°C.) (Note 2) A A PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS DYNAMIC Turn-On Time t V or V = 1.0V, R = 50Ω, Figure 1 90 250 ns ON NO_ NC_ L Turn-Off Time t V or V = 1.0V, R = 50Ω, Figure 1 10 50 ns OFF NO_ NC_ L Propagation Delay t R = R = 50Ω, unbalanced, Figure 2 50 ps PD S L R = R = 50Ω , unba
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5.0Gbps PCI Express Passive Switches Typical Operating Characteristics (T = +25°C, unless otherwise noted.) A ON-RESISTANCE vs. V ON-RESISTANCE vs. V COM COM ON-RESISTANCE vs. V (V+ = 1.8V) (V+ = 2.5V) COM 10.0 14 14 T = +85°C T = +85°C V+ = 1.8V A A 9.5 12 12 T = +25°C A 9.0 T = +25°C A 10 10 8.5 V+ = 2.5V 8.0 8 8 7.5 6 6 7.0 T = -40°C A 6.5 4 4 V+ = 3.3V 6.0 2 2 T = -40°C A 5.5 5.0 0 0 -0.1 0.1 0.3 0.5 0.7 0.9 1.1 1.3 1.5 1.7 1.9 2.1 -0.1 0 0.1 0.2 0.3 0.4 0.5 0.6 -0.1 0.1 0.3 0.5 0.7 0.9 1.1
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MAX4888A/MAX4889A 5.0Gbps PCI Express Passive Switches Typical Operating Characteristics (continued) (T = +25°C, unless otherwise noted.) A EYE DIAGRAM EYE DIAGRAM EYE DIAGRAM (V+ = 1.8V, f = 1.25GHz, (V+ = 2.5V, f = 1.25GHz, (V+ = 3.3V, f = 1.25GHz, † † † 600mV PRBS SIGNAL, R = R = 50Ω) 600mV PRBS SIGNAL, R = R = 50Ω) 600mV PRBS SIGNAL, R = R = 50Ω) P-P S L P-P S L P-P S L V V V COM_+ COM_+ COM_+ 50mV/div 50mV/div 50mV/div V V V COM_- COM_- COM_- 50ps/div 50ps/div 50ps/div *PRBS = PSEUDORAND
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5.0Gbps PCI Express Passive Switches Pin Description PIN NAME FUNCTION MAX4888A MAX4889A 1, 10, 12, 14, 1, 4, 10, 14, 17, GND Ground 20, 25, 27 19, 21, 39, 41 2 9 SEL Digital Control Input 3, 9 — N.C. No Connection. Not internally connected. 4 2 COM1+ Analog Switch 1. Common Positive Terminal. 5 3 COM1- Analog Switch 1. Common Negative Terminal. 6 6 COM2+ Analog Switch 2. Common Positive Terminal. 7 7 COM2- Analog Switch 2. Common Negative Terminal. 5, 8, 13, 18, Positive-Supply Voltage Input. C
Summary of the content on the page No. 7
MAX4888A/MAX4889A 5.0Gbps PCI Express Passive Switches Test Circuits/Timing Diagrams MAX4888A/MAX4889A 3.3V t < 5ns r V IH t < 5ns f LOGIC 50% V+ INPUT V IL NO_ COM_ V N_ V OUT OR NC_ t OFF R C L L SEL V OUT 0.9 x V 0.9 x V 0UT OUT GND LOGIC SWITCH 0V INPUT OUTPUT t ON C INCLUDES FIXTURE AND STRAY CAPACITANCE. L R L V = V OUT N_ ( ) R + R L ON V = V OR V N_ NO_ NC_ Figure 1. Switching Time __________________________________________________________________________
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5.0Gbps PCI Express Passive Switches Test Circuits/Timing Diagrams (continued) 3.3V V+ MAX4888A/MAX4889A NO_+ OR R S COM NC_+ _+ IN+ OUT+ RISE-TIME PROPAGATION DELAY = t OR t PLHX PLHY FALL-TIME PROPAGATION DELAY = t OR t PHLX PHLY R L t = DIFFERENCE IN PROPAGATION DELAY (RISE-FALL) SK1 BETWEEN ANY TWO PAIRS NO_- OR R S COM NC_- _- t = | t - t | OR | t - t | SK2 PLHX PHLY PHLX PLHY IN- OUT- BETWEEN TWO LINES ON THE SAME PAIR R L SEL t INFALL t INRISE 1.5V 90% 90% V IN+ 50% 50% 10% 10% 0V 1.5V
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MAX4888A/MAX4889A 5.0Gbps PCI Express Passive Switches Test Circuits/Timing Diagrams (continued) 3.3V 0.1μF V OUT OFF-ISOLATION = 20log V IN NETWORK ANALYZER 50Ω 50Ω V OUT V+ V ON-LOSS = 20log 0V OR V+ IN SEL V IN COM_ V MAX4888A/MAX4889A OUT CROSSTALK = 20log NC_ V IN V MEAS REF OUT NO_ 50Ω 50Ω 50Ω GND MEASUREMENTS ARE STANDARDIZED AGAIN
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5.0Gbps PCI Express Passive Switches Functional Diagrams/Truth Table V+ V+ MAX4888A MAX4889A COM1+ NC1+ COM1+ NC1+ COM1- NC1- COM1- NC1- NO1+ NO1+ NO1- NO1- COM2+ COM2+ NC2+ NC2+ COM2- NC2- COM2- NC2- NO2+ NO2+ NO2- NO2- SEL COM3+ NC3+ COM3- NC3- GND NO3+ NO3- COM__TO COM__TO COM4+ NC4+ SEL NC__ NO__ COM4- NC4- 0 ON OFF 1 OFF ON NO4+ NO4- SEL GND 10 ______________________________________________________________________________________ MAX4888A/MAX4889A
Summary of the content on the page No. 11
MAX4888A/MAX4889A 5.0Gbps PCI Express Passive Switches Applications Information DATA PCIe Switching DIRECTION The MAX4888A/MAX4889A primary applications are aimed at reallocating PCIe lanes (see Figure 5). For MAX4888A example, in graphics applications, several manufacturers ONE LANE MAX4889A have found that it is possible to improve performance by a factor of nearly two by splitting a single 16-lane PCIe bus into two 8-lane buses. Two of the more promi- nent examples are SLI™ (Scaled Link Inter
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5.0Gbps PCI Express Passive Switches Typical Application Circuit PCIe GRAPHICS INTERFACE GRAPHICS GRAPHICS CARD 1 CARD 2 PCIe BUS COM1+ NC1+ LANE 0 TX COM1- NC1- COM2+ NC2+ LANE 1 TX COM2- MAX4889A NC2- COM3+ NC3+ LANE 2 TX COM3- NC3- COM4+ NC4+ LANE 3 TX COM4- NC4- NO1+ NO1- NO2+ NO2- NO3+ NO3- NO4+ NO4- SEL CHANNEL SELECT COM1+ NC1+ LANE 0 RX COM1- NC1- COM2+ NC2+ LANE 1 RX COM2- MAX4889A NC2- COM3+ NC3+ LANE 2 RX COM3- NC3- COM4+ NC4+ LANE 3 RX COM4- NC4- NO1+ NO1- NO2+ NO2- NO3+ NO3- NO4+ NO
Summary of the content on the page No. 13
MAX4888A/MAX4889A 5.0Gbps PCI Express Passive Switches Package Information (The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information go to www.maxim-ic.com/packages.) ° ______________________________________________________________________________________ 13 28L THIN QFN.EPS
Summary of the content on the page No. 14
5.0Gbps PCI Express Passive Switches Package Information (continued) (The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information go to www.maxim-ic.com/packages.) ° Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circu Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit pa
