MAX14978ETO

19-5573; Rev 1; 4/11 SuperSpeed USB Passive Switch (Low/Full/Hi/SuperSpeed) General Description The MAX14978 high-performance, passive analog switch is ideal for switching Hi-Speed USB and SuperSpeed USB data between one source and two loads, or vice versa. The device can be used in desktop and notebook applications where SuperSpeed USB ports are in limited supply. The device consists of two sets of analog switches with one set used for USB low-speed, full-speed, and Hi-Speed signals and the second set used for USB SuperSpeed. The device operates from a single +3.3V supply. The device features low insertion loss for all speeds. It has Q6kV Human Body Model (HBM) ESD protection on all I/O pins. In addition, the low/full/Hi-Speed COM_ ports have ESD protection to Q15kV HBM and Q8kV IEC 61000-4-2 contact. The device is available in a small, 3.5mm x 9.0mm, 42-pin TQFN package and is specified over the extended -40NC to +85NC temperature range. Features S Designed for SuperSpeed USB Applications: MAX14978 Low/Full/Hi-Speed (1.5/12/480Mbps) SuperSpeed (5.0Gbps) S Superior Return Loss and Insertion Loss for SuperSpeed Analog Switches S Low Quiescent Current: 36µA (typ) S All Link Training is Preserved (SuperSpeed) S LVCMOS Control (1.4V P VIH P 3.6V) S Operation from a Single +3.3V Power Supply S Small, 3.5mm x 9.0mm, 42-Pin TQFN Package Ordering Information PART MAX14978ETO+ TEMP RANGE -40NC to +85NC PIN-PACKAGE 42 TQFN-EP* Applications Desktop PCs Laptop PCs Industrial USB Switching +Denotes a lead(Pb)-free/RoHS-compliant package. *EP = Exposed pad. Typical Operating Circuit +3.3V USB SWITCH CONTROLLER SEL1 SEL2 VCC VDD NCD+ NCDNOD+ NOD0.1µF D+ DSUPERSPEED Tx+ USB CONTROLLER TxRx+ Rx- COMD+ COMDCOM0+ COM0COM1+ COM1- MAX14978 NC0+ NC0NC1+ NC1NO0+ NO0NO1+ NO1- D+ DSUPERSPEED Tx+ USB TxPORT1 Rx+ Rx- EN GND D+ DTx+ SUPERSPEED USB TxPORT2 Rx+ Rx- _______________________________________________________________ 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. SuperSpeed USB Passive Switch (Low/Full/Hi/SuperSpeed) MAX14978 ABSOLUTE MAXIMUM RATINGS (All voltages referenced to GND, unless otherwise noted.) VCC ....................................................................... -0.3V to +6.0V VDD ....................................................................... -0.3V to +4.0V SEL1, EN, COMD_, NOD_, NCD_ (Note 1) ...................................... -0.3V to (VCC + 0.3V) SEL2, COM0_, COM1_, NC0_, NC1_, NO0_, NO1_ (Note 1) ............... -0.3V to (VDD + 0.3V) |COM0_ - NO0_|, |COM0_ - NC0_|, |COM0 _ - NO1 _|, |COM0 _ - NC1_| (Note 1) ........ 0 to +2.0V Continuous Current (COM0_, COM1_ to NO0_, NO1_, NC0_, NC1_) ........................ Q70mA Peak Current (COM0_, COM1_ to NO0_, NO1_, NC0_, NC1_) (pulsed at 1ms, 10% duty cycle) ................................. Q70mA Continuous Current into Any Terminal ............................ Q30mA Continuous Power Dissipation (TA = +70NC) TQFN (derate 35.7mW/NC above +70NC) .................. 2857mW Operating Temperature Range .......................... -40NC to +85NC Storage Temperature Range............................ -65NC to +150NC Junction Temperature .....................................................+150NC Lead Temperature (soldering, 10s) ................................+300NC Soldering Temperature (reflow) ......................................+260NC Note 1: Signals on SEL_, NO_, NC_, or COM_ exceeding VCC, VDD, or VGND are clamped by internal diodes. Limit forward-diode current to maximum current rating. Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability. ELECTRICAL CHARACTERISTICS (VCC = +3.0V to +5.5V, VDD = +3.0V to +3.6V, TA = -40NC to +85NC, unless otherwise noted. Typical values are at VCC = VDD = +3.3V, TA = +25NC.) (Note 2) PARAMETER Power-Supply Range Supply Current Shutdown Supply Current, ICC Increase in Supply Current, ICC, with VSEL1, VEN Voltage VCOM_, VNO_, VNC_ VFP SYMBOL VCC VDD ICC IDD ISHDN VSEL1 = 0V or VCC, VEN = 0V VCC = 3.0V VSEL2 = 0V or VDD VDD = 3.3V 0.1 Hi-Speed USB switches, switch disabled (VEN = VCC) Hi-Speed USB switches, 0V P VSEL1 P VIL or VIH P VSEL1 P VCC or 0V P VEN P VIL or VIH P VEN P VCC Hi-Speed USB switches, VEN = 0V (Note 3) SuperSpeed USB switches Hi-Speed USB switches, COMD_ only, TA = +25NC Hi-Speed USB switches, VCOMD_ = 0V to VCC On-Resistance RON Hi-Speed USB switches, VCC = 3.0V, VCOMD_ = 3.6V SuperSpeed USB switches, VDD = 3.0V, ICOM_ = 15mA, VNO_ = VNC_ = 0V, 1.8V 0 -0.3 VCC + 0.6 VCC + 0.8 5 5.5 7 CONDITIONS MIN 3.0 3.0 0.6 TYP MAX 5.5 3.6 1.5 60 UNITS V FA FA 1 FA VCC VDD 1.2 VCC +1 10 I V Analog Signal Range Fault-Protection Trip Threshold V 2 SuperSpeed USB Passive Switch (Low/Full/Hi/SuperSpeed) ELECTRICAL CHARACTERISTICS (continued) (VCC = +3.0V to +5.5V, VDD = +3.0V to +3.6V, TA = -40NC to +85NC, unless otherwise noted. Typical values are at VCC = VDD = +3.3V, TA = +25NC.) (Note 2) PARAMETER SYMBOL CONDITIONS Hi-Speed USB switches, VCC = 3.0V, VCOMD_ = 2.0V (Notes 4, 5) DRON SuperSpeed USB switches, VDD = 3.0V, ICOM_ = 15mA, VNO_ or VNC_ = 0V (Notes 4, 5) SuperSpeed USB switches, VDD = 3.0V, ICOM_ = 15mA, VNO_ or VNC_ = 0V (Notes 4, 5) Hi-Speed USB switches, VCC = 3.0V, VCOMD_ = 0V to VCC (Note 6) On-Resistance Flatness RFLAT SuperSpeed USB switches, VDD = 3.0V, ICOM_ = 15mA, VNO_ or VNC_= 0V (Notes 5, 6) Hi-Speed USB switches, VCC = 5.5V, VCOMD_ = 0V or 5.5V, VNOD_, VNCD_ = 5.5V or 0V SuperSpeed USB switches, VDD = 3.6V, VCOM_ = 0V, 1.8V; VNO_ or VNC_ = 1.8V, 0V Hi-Speed USB switches, VCC = 5.5V, VCOMD_ = 0V or 5.5V, VNOD_, VNCD_ = unconnected SuperSpeed USB switches, VDD = 3.6V, VCOM_ = 0V, 1.8V; VNO_ or VNC_ = VCOM_ or unconnected Hi-Speed USB switches, RL = RS = 50I, signal = 0dBm SuperSpeed USB switches, RL = RS = 50I, unbalanced Hi-Speed USB switches, VNOD_, VNCD_ = 0dBm, RL = RS = 50I, Figure 1 SuperSpeed USB switches, signal = 0dBm, RS = RL = 50I 1MHz < f < 100MHz 500MHz < f < 1.25GHz f = 10MHz f = 250MHz f = 500MHz f = 10MHz f = 1.25GHz -250 MIN TYP 0.1 MAX 1 I 0.6 2 UNITS MAX14978 On-Resistance Match Between Channels On-Resistance Match Between Pairs of Same Channels DRON 0.1 1 I 0.1 I 0.06 2 +250 nA Off-Leakage Current ICOM(OFF) -1 +1 FA -250 +250 nA On-Leakage Current ICOM(ON) -1 +1 FA AC PERFORMANCE On-Channel -3dB Bandwidth BW 950 -0.5 dB -1.4 -48 -20 -17 -56 -26 dB MHz On-Loss GLOSS Off-Isolation VISO 3 SuperSpeed USB Passive Switch (Low/Full/Hi/SuperSpeed) MAX14978 ELECTRICAL CHARACTERISTICS (continued) (VCC = +3.0V to +5.5V, VDD = +3.0V to +3.6V, TA = -40NC to +85NC, unless otherwise noted. Typical values are at VCC = VDD = +3.3V, TA = +25NC.) (Note 2) PARAMETER SYMBOL CONDITIONS Hi-Speed USB switches, VNOD_, VNCD_= 0dBm, RL = RS = 50I, Figure 1 Crosstalk (Note 7) VCT SuperSpeed USB switches, crosstalk between any two pairs, RS = RL = 50I, unbalanced, Figure 1 f = 10MHz f = 250MHz f = 500MHz f = 50MHz f = 1.25GHz MIN TYP -73 -54 -33 -53 -32 5.0 1.4 0.5 Hi-Speed USB switches Input Leakage Current Input Logic Hysteresis DYNAMIC PERFORMANCE Hi-Speed USB switches, VNOD_ or VNCD_ = 1.5V, RL = 300I, CL = 35pF, VEN = VCC to 0V, Figure 2 SuperSpeed USB switches, VNO_ or VNC_ = 1.0V, RL = 50I, Figure 2 VNOD_ or VNCD_ = 1.5V, RL = 300I, CL = 35pF, VEN = 0V to VCC, Figure 2 SuperSpeed USB switches, VNO_ or VNC_ = 1.0V, RL = 50I, Figure 2 Hi-Speed USB switches, RL = RS = 50I, Figure 3 SuperSpeed USB switches, RL = RS = 50I Output Skew Between Switches tSK Hi-Speed USB switches, skew between switch 1 and 2, RL = RS = 50I, Figure 3 SuperSpeed USB switches, RS = RL = 50I, unbalanced; skew between any two pairs, Figure 3 SuperSpeed USB switches, RS = RL = 50I, unbalanced; skew between two lines on same pair, Figure 3 Hi-Speed USB switches, VCOMD_ = 0V to 5V step, RL = RS = 50I, VCC = 3.3V, Figure 4 0.5 20 100 Fs IIN VHYST SuperSpeed USB switches, VSEL2 = 0V or VDD SuperSpeed USB switches -250 -1 100 +250 +1 Gbps V V nA FA mV dB MAX UNITS Signaling Data Rate LOGIC INPUT Input Logic-High Input Logic-Low BR VIH VIL SuperSpeed USB switches, RS = RL = 50I Turn-On Time tON 90 1 10 100 50 40 250 5 50 ns Fs ns Turn-Off Time tOFF Propagation Delay tPLH, tPHL ps ps Output Skew Between Pairs tSK1 50 ps Output Skew Between Same Pair tSK2 10 ps Fault-Protection Response Time tFP 5.0 Fs 4 SuperSpeed USB Passive Switch (Low/Full/Hi/SuperSpeed) ELECTRICAL CHARACTERISTICS (continued) (VCC = +3.0V to +5.5V, VDD = +3.0V to +3.6V, TA = -40NC to +85NC, unless otherwise noted. Typical values are at VCC = VDD = +3.3V, TA = +25NC.) (Note 2) PARAMETER SYMBOL CONDITIONS Hi-Speed USB switches, VCOMD_ = 5V to 0V step, RL = RS = 50I, VCC = 3.3V, Figure 4 Hi-Speed USB switches, f = 1MHz, Figure 5 SuperSpeed USB switches, Figure 5 Hi-Speed USB switches, f = 1MHz, Figure 5 Hi-Speed USB switches, f = 240MHz, Figure 5 Hi-Speed USB switches, f = 1MHz, Figure 5 COM_ On-Capacitance CCOM(ON) Hi-Speed USB switches, f = 240MHz, Figure 5 SuperSpeed USB switches, Figure 5 Total Harmonic Distortion Plus Noise ESD PROTECTION Human Body Model COMD+, COMDCOM0_, COM1_ All Pins Note Note Note Note Note 2: 3: 4: 5: 6: IEC 61000-4-2 Air Gap Discharge IEC 61000-4-2 Contact Discharge Human Body Model Human Body Model ±15 ±15 ±8 ±6 ±2 kV kV kV THD+N Hi-Speed USB switches, VCOMD_ = 1VP-P, VBIAS = 1V, RL = RS = 50I, f = 20Hz to 20kHz 2 1 5.5 pF 4.8 6.5 5.5 2 0.03 % pF MIN TYP MAX UNITS MAX14978 Fault-Protection Recovery Time tFPR 100 Fs NO_ or NC_ Off-Capacitance CNO(OFF) or CNC(OFF) pF COM_ Off-Capacitance CCOM(OFF) All devices are 100% production tested at TA = +25NC. All temperature limits are guaranteed by design. The switch turns off for voltages above VFP, protecting downstream circuits in case of a fault condition. DRON(MAX) = |RON(CH1) - RON(CH2)|. Guaranteed by design. Not production tested. Flatness is defined as the difference between the maximum and minimum value of on-resistance, as measured over specified analog-signal ranges. Note 7: Between any two switches. 5 SuperSpeed USB Passive Switch (Low/Full/Hi/SuperSpeed) MAX14978 Test Circuits/Timing Diagrams 0.1µF VCC VDD 0.1µF NETWORK ANALYZER 0V OR VDD SEL_ VCC VDD COM_ VIN 50Ω 50Ω V OFF-ISOLATION = 20log OUT VIN V ON-LOSS = 20log OUT VIN V CROSSTALK = 20log OUT VIN NC_ 50Ω MAX14978 NO_ VOUT MEAS 50Ω GND REF 50Ω MEASUREMENTS ARE STANDARDIZED AGAINST SHORTS AT IC TERMINALS. OFF-ISOLATION IS MEASURED BETWEEN COM_ AND "OFF" NO_ OR NC_ TERMINAL ON EACH SWITCH. ON-LOSS IS MEASURED BETWEEN COM_ AND "ON" NO_ OR NC_ TERMINAL ON EACH SWITCH. CROSSTALK IS MEASURED BETWEEN ANY TWO PAIRS. SIGNAL DIRECTION THROUGH SWITCH IS REVERSED; WORST VALUES ARE RECORDED. Figure 1. Off-Isolation, On-Loss, and Crosstalk 0.1µF VDD VCC 0.1µF t r < 5 ns t f < 5 ns VDD VCC MAX14978 NO_ OR NC_ SEL_ LOGIC INPUT GND COM_ RL CL LOGIC INPUT VOUT VIH VIL 50% VN_ t OFF VOUT SWITCH OUTPUT 0V t ON 0.9 x V0UT 0.9 x VOUT CL INCLUDES FIXTURE AND STRAY CAPACITANCE. VOUT = VN_ (RL + LRON) R VN_ = VNO_ OR VNC_ Figure 2. Switching Time 6 SuperSpeed USB Passive Switch (Low/Full/Hi/SuperSpeed) Test Circuits/Timing Diagrams (continued) 0.1µF VDD VCC 0.1µF MAX14978 VDD VCC NO_+ OR NC_+ MAX14978 COM_+ RL RS NO_- OR NC_COM_RL SEL_ tINRISE +1.5V VIN+ 0V +1.5V VIN0V tOUTRISE tPLHX +1.5V VOUT+ 0V +1.5V VOUT0V tPHLY tPLHY 50% 50% 50% 50% 10% 10% tPHLX 90% 90% tOUTFALL 50% 50% 50% 50% 10% 10% tINFALL OUT+ RISE-TIME PROPAGATION DELAY = tPLHX OR tPLHY FALL-TIME PROPAGATION DELAY = tPHLX OR tPHLY tSK1 = DIFFERENCE IN PROPAGATION DELAY (RISE-FALL) BETWEEN ANY TWO PAIRS OUTtSK2 = | tPLHX - tPHLY | OR | tPHLX - tPLHY | BETWEEN TWO LINES ON THE SAME PAIR IN+ RS IN- 90% 90% Figure 3. Propagation Delay, Output Skew 7 SuperSpeed USB Passive Switch (Low/Full/Hi/SuperSpeed) MAX14978 Test Circuits/Timing Diagrams (continued) VCC = +3.3V +5V +3V VCOMD_ tFP tFPR CAPACITANCE METER VFP VNOD_ VNCD_ +3V 0V 0V VDD COM_ VCC MAX14978 SEL_ NC_ OR NO_ GND VIL OR VIH 0.1µF VDD VCC 0.1µF Figure 4. Fault Protection Response/Recovery Time Figure 5. Channel Off-/On-Capacitance Typical Operating Characteristics (VCC = VDD = 3.3V, TA = +25NC, unless otherwise noted.) EYE DIAGRAM (VCC = +3.3V, f = 2.5GHz, RS = RL = 50Ω) MAX14978 toc01 SUPERSPEED SWITCHES ON-RESISTANCE vs. VCOM_ MAXMAX14978 toc02 SUPERSPEED SWITCHES ON-RESISTANCE vs. VCOM_ (VCC = +3.3V) 12 TA = +25°C 10 RON (Ω) 8 6 4 TA = +85°C MAX14978 toc03 800 600 400 VOLTAGE (mV) 200 0 -200 -400 -600 -800 10.0 9.5 9.0 8.5 RON (Ω) 8.0 7.5 7.0 6.5 6.0 5.5 5.0 VCC = +3.3V 14 EYE: ALL BITS Uls: 9995/9995 2 0 TA = -40°C -0.1 0.1 0.3 0.5 0.7 0.9 1.1 1.3 1.5 1.7 1.9 2.1 VCOM_ (V) -200 -150 -100 -50 0 ps/div 50 100 150 200 -0.1 0.1 0.3 0.5 0.7 0.9 1.1 1.3 1.5 1.7 1.9 2.1 VCOM_ (V) 8 SuperSpeed USB Passive Switch (Low/Full/Hi/SuperSpeed) Typical Operating Characteristics (continued) (VCC = VDD = 3.3V, TA = +25NC, unless otherwise noted.) SUPERSPEED HI-SPEED SWITCHES SUPPLY CURRENT vs. TEMPERATURE MAX14978 toc04 MAX14978 SUPERSPEED SWITCHES LOGIC-INPUT THRESHOLD vs. SUPPLY VOLTAGE MAX14978 toc05 LOW/FULL/HI-SPEED SWITCHES ON-RESISTANCE vs. VCOM_ 6 5 RON (Ω) 4 3 2 1 0 TA = +85°C TA = +25°C TA = -40°C MAX14978 toc06 80 70 SUPPLY CURRENT (µA) 60 50 40 30 20 10 0 -40 -15 10 35 TEMPERATURE (°C) 60 VCC = +3.3V 1.2 1.1 LOGIC THRESHOLD (V) 1.0 0.9 0.8 0.7 0.6 0.5 VIL VIH 7 85 1.6 1.8 2.0 2.2 2.4 2.6 2.8 3.0 3.2 3.4 3.6 SUPPLY VOLTAGE (V) 0 1 VCOM_ (V) 2 3 LOW/FULL/HI-SPEED SWITCHES COM_ LEAKAGE CURRENT vs. TEMPERATURE MAX14978 toc07 LOW/FULL/HI-SPEED SWITCHES QUIESCENT SUPPLY CURRENT vs. LOGIC LEVEL MAX14978 toc08 LOW/FULL/HI-SPEED SWITCHES LOGIC-INPUT THRESHOLD vs. SUPPLY VOLTAGE MAX14978 toc09 80 70 LEAKAGE CURRENT (nA) 60 50 40 30 20 10 0 -40 -15 10 35 60 COM_ OFF-LEAKAGE COM_ ON-LEAKAGE 5 QUIESCENT SUPPLY CURRENT (µA) 4 3 2 1 0 1.2 1.0 LOGIC THRESHOLD (V) 0.8 0.6 0.4 0.2 0 2.8 3.8 4.8 SUPPLY VOLTAGE (V) VIH VIL 85 0 1 2 3 TEMPERATURE (°C) LOGIC LEVEL (V) LOW/FULL/HI-SPEED SWITCHES FREQUENCY RESPONSE MAX14978 toc10 LOW/FULL/HI-SPEED SWITCHES TOTAL HARMONIC DISTORTION PLUS NOISE vs. FREQUENCY RL = 600Ω MAX14978 toc11 0 -10 -20 -30 MAGNITUDE (dB) ON-LOSS OFF-ISOLATION 1 -50 -60 -70 -80 -90 -100 CROSSTALK THD+N (%) -40 0.1 0.01 0.001 1 10 100 1,000 10 100 1000 FREQUENCY (Hz) 10,000 100,000 FREQUENCY (MHz) 9 SuperSpeed USB Passive Switch (Low/Full/Hi/SuperSpeed) MAX14978 Pin Configuration TOP VIEW NOD+ NCD+ NCDNODNC0+ NC1+ NO0+ NO1+ EP NC0- NC1- NO0- 38 37 36 35 34 33 32 31 30 29 28 27 26 25 24 23 22 N.C. 39 N.C. 40 N.C. 41 N.C. 42 1 N.C. MAX14978 21 GND 20 VDD 19 GND 18 VDD + 2 N.C. 3 N.C. 4 COMD+ 5 GND 6 N.C. 7 COMD8 N.C. 9 SEL2 COM0+ COM0GND GND COM1+ VDD 10 11 12 13 14 15 16 17 COM1GND TQFN NO1- SEL1 N.C. VCC VDD EN Pin Description PIN 1, 2, 3, 6, 8, 36, 39-42 4 5, 10, 14, 17, 19, 21 7 9 11 12 13, 18, 20, 30 15 16 22 23 24 25 26 27 28 29 31 32 NAME N.C. COMD+ GND COMDSEL2 COM0+ COM0VDD COM1+ COM1NO1NO1+ NO0NO0+ NC1NC1+ NC0NC0+ NODNCDNo Connection. Not internally connected. Hi-Speed USB Analog Switch, Common D+ Terminal Ground Hi-Speed USB Analog Switch, Common D- Terminal Digital Control Input for SuperSpeed USB Analog Switches SuperSpeed USB Analog Switch 0, Common Positive Terminal SuperSpeed USB Analog Switch 0, Common Negative Terminal Positive Supply Voltage Input for SuperSpeed USB Switches. Bypass VDD to GND with a 0.1FF ceramic capacitor as close as possible to the device. SuperSpeed USB Analog Switch 1, Common Positive Terminal SuperSpeed USB Analog Switch 1, Common Negative Terminal SuperSpeed USB Analog Switch 1, Normally Open Negative Terminal SuperSpeed USB Analog Switch 1, Normally Open Positive Terminal SuperSpeed USB Analog Switch 0, Normally Open Negative Terminal SuperSpeed USB Analog Switch 0, Normally Open Positive Terminal SuperSpeed USB Analog Switch 1, Normally Closed Negative Terminal SuperSpeed USB Analog Switch 1, Normally Closed Positive Terminal SuperSpeed USB Analog Switch 0, Normally Closed Negative Terminal SuperSpeed USB Analog Switch 0, Normally Closed Positive Terminal Hi-Speed USB Analog Switch, Normally Open D- Terminal Hi-Speed USB Analog Switch, Normally Closed D- Terminal FUNCTION 10 SuperSpeed USB Passive Switch (Low/Full/Hi/SuperSpeed) Pin Description (continued) PIN 33 34 35 37 38 — NAME EN VCC SEL1 NCD+ NOD+ EP FUNCTION Active-Low Enable Input for Hi-Speed USB Switches. Drive EN high to put Hi-Speed USB switches in high impedance. Drive EN low for normal operation. Positive-Supply Voltage Input for Hi-Speed USB Switches. Bypass VCC to GND with a 0.1FF ceramic capacitor as close as possible to the device. Digital Control Input for Hi-Speed USB Analog Switches Hi-Speed USB Analog Switch, Normally Closed D+ Terminal Hi-Speed USB Analog Switch, Normally Open D+ Terminal Exposed Pad. EP is internally connected to GND. Connect EP to a large ground plane to maximize thermal performance. EP is not intended as an electrical connection point. MAX14978 Functional Diagram/Truth Table HI-SPEED USB SWITCHES VCC VDD EN 0 0 1 NOD+ NCD+ NODNCD- SEL1 0 1 X NOD_ OFF ON OFF NCD_ ON OFF OFF COMD_ — — HIGH-Z MAX14978 HI-SPEED USB ANALOG SWITCHES COMD+ COMDSEL1 EN SUPERSPEED USB ANALOG SWITCHES COM0+ COM0COM1+ COM1SEL2 SUPERSPEED USB SWITCHES SEL2 0 1 NO_ OFF ON NC_ ON OFF NO0+ NC0+ NO0NC0NO1+ NC1+ NO1NC1- GND 11 SuperSpeed USB Passive Switch (Low/Full/Hi/SuperSpeed) MAX14978 Detailed Description The MAX14978 is ideal for SuperSpeed USB and low/ full/Hi-Speed (1.5/12/480Mbps) USB switching applications. The low VIH threshold of the device permits it to be used with logic levels as low as 1.4V. The device’s Hi-Speed USB analog switches are based on a chargepump-assisted n-channel architecture and operate with 36FA (typ) quiescent current. The device features dual digital control inputs (SEL_) to switch Hi-Speed USB and SuperSpeed USB signal paths separately. The device’s provides dual digital control inputs (SEL1, SEL2) to select the signal path between the COM_ and NO_ or NC_ channels. Drive SEL1 and SEL2 rail-to-rail to minimize power consumption. See the Functional Diagram/Truth Table. The device’s switches are bidirectional, allowing NO_, NC_, and COM_ to be configured as either inputs or outputs. The Hi-Speed USB switches are equipped with a chargepump-assisted n-channel architecture that allows the switch to pass analog signals that exceed VCC up to the overvoltage fault-protection threshold. This allows USB signals that exceed VCC to pass, allowing compliance with USB requirements for voltage levels. The SuperSpeed USB switches accept signals on the COM_, NO_, and NC_ channels within a range of -0.1V to (VDD - 1.2V). Signals on the COM_+ channels are routed to either the NO_+ or NC_+ channels, and signals on the COM_- channels are routed to either the NO_- or NC_- channels. The device features overvoltage fault protection on COMD_. Fault protection prevents these switches from being damaged due to shorts to the USB VBUS voltage rail. Fault protection protects the switch and USB transceiver from damaging voltage levels. When voltages on COMD_ exceed the fault-protection threshold (VFP), COMD_, NCD_ and NOD_ are high impedance. The device features a shutdown mode for the Hi-Speed USB analog switches that reduces the VCC quiescent current to 0.1FA (typ) and places COMD+ and COMDin high impedance. Drive EN high to place the Hi-Speed USB analog switches in shutdown mode, and drive EN low for normal operation. Enable Input Applications Information The device’s analog switches are fully compliant with the USB 2.0 and USB 3.0 specifications. The low on-resistance and low on-capacitance of these switches make them ideal for high-performance switching applications. The device is ideal for routing USB data lines and for applications that require switching between multiple USB hosts or devices. The device’s Hi-Speed USB analog switches also feature overvoltage fault protection to guard systems against shorts to the USB VBUS voltage rail that is required for all Hi-Speed USB applications. As with all Maxim devices, ESD protection structures are incorporated on all pins to protect against electrostatic discharges encountered during handling and assembly. COMD+ and COMD- are further protected against static electricity. Maxim’s engineers have developed state-ofthe-art structures to protect these pins against ESD up to Q15kV without damage. The ESD structures withstand high ESD in normal operation and when the device is powered down. After an ESD event, the device continues to function without latchup. The device is characterized for protection to the following limits: • Q15kV using Human Body Model • Q15kV using IEC 61000-4-2 Air Gap Discharge method • Q8kV using IEC 61000-4-2 Contact Discharge method Note: High ESD performance is only applicable to the Hi-Speed USB section of the switch. The SuperSpeed USB section is rated to Q6kV HBM. USB Switching Digital Control Inputs (SEL1, SEL2) Analog-Signal Levels Extended ESD Protection Overvoltage Fault Protection 12 SuperSpeed USB Passive Switch (Low/Full/Hi/SuperSpeed) ESD performance depends on a variety of conditions. Contact Maxim for a reliability report that documents test setup, test methodology, and test results. Figure 6a shows the Human Body Model, and Figure 6b shows the current waveform it generates when discharged into a low-impedance state. This model consists of a 100pF capacitor charged to the ESD voltage of interest, which is then discharged into the test device through a 1.5kI resistor. ESD Test Conditions lower than that measured using the Human Body Model. Figure 7b shows the current waveform for the Q8kV IEC 61000-4-2 Level 4 ESD Contact Discharge test. The Air Gap Discharge test involves approaching the device with a charged probe. The Contact Discharge method connects the probe to the device before the probe is energized. High-speed switches require proper layout and design procedures for optimum performance. Keep designcontrolled impedance PCB traces as short as possible or follow impedance layouts per the SuperSpeed USB specification. Ensure that power-supply bypass capacitors are placed as close as possible to the device. Multiple bypass capacitors are recommended. Connect all grounds and the exposed pad to large ground planes where possible. MAX14978 Human Body Model Layout The main difference between tests done using the Human Body Model and IEC 61000-4-2 is higher peak current in IEC 61000-4-2. Because series resistance is lower in the IEC 61000-4-2 ESD test model (Figure 7a) the ESDwithstand voltage measured to this standard is generally IEC 61000-4-2 RC 1MΩ CHARGE-CURRENTLIMIT RESISTOR HIGHVOLTAGE DC SOURCE RD 1500Ω DISCHARGE RESISTANCE DEVICE UNDER TEST HIGHVOLTAGE DC SOURCE RC 50MΩ TO 100MΩ CHARGE-CURRENTLIMIT RESISTOR RD 330Ω DISCHARGE RESISTANCE DEVICE UNDER TEST CS 100pF STORAGE CAPACITOR CS 150pF STORAGE CAPACITOR Figure 6a. Human Body ESD Test Model Figure 7a. IEC 61000-4-2 ESD Test Model IP 100% 90% AMPERES 36.8% 10% 0 0 tRL IR PEAK-TO-PEAK RINGING (NOT DRAWN TO SCALE) IPEAK I 100% 90% 10% TIME tDL CURRENT WAVEFORM tR = 0.7ns TO 1ns 30ns 60ns t Figure 6b. Human Body Current Waveform Figure 7b. IEC 61000-4-2 ESD Generator Current Waveform 13 SuperSpeed USB Passive Switch (Low/Full/Hi/SuperSpeed) MAX14978 Power-Supply Sequencing Caution: Do not exceed the absolute maximum ratings because stresses beyond the listed ratings may cause permanent damage to the device. Proper power-supply sequencing is recommended for all CMOS devices. Always apply VCC and VDD before applying analog signals, especially if the analog signals are not current limited. Package Information For the latest package outline information and land patterns (footprints), go to www.maxim-ic.com/packages. Note that a “+”, “#”, or “-” in the package code indicates RoHS status only. Package drawings may show a different suffix character, but the drawing pertains to the package regardless of RoHS status. PACKAGE TYPE 42 TQFN-EP PACKAGE CODE T423590M+1 OUTLINE NO. 21-0181 LAND PATTERN NO. 90-0079 14 SuperSpeed USB Passive Switch (Low/Full/Hi/SuperSpeed) MAX14978 Revision History REVISION NUMBER 0 1 REVISION DATE 9/10 4/11 Initial release Updated analog signal range specification in Electrical Characteristics DESCRIPTION PAGES CHANGED — 2 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. Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 © 15 2011 Maxim Integrated Products Maxim is a registered trademark of Maxim Integrated Products, Inc.