PI6C557-03AQ PCIe 2.0 Clock Generator with 2 HCSL Outputs for Automotive Applications Features Description IIPCIe(R) 2.0 compliant The PI6C557-03AQ is a spread spectrum clock generator compliant to PCI Express(R) 2.0 and Ethernet requirements. The device is used for PC or embedded systems to substantially reduce Electromagnetic Interference (EMI). aa Phase jitter - 2.1ps RMS (typ) IILVDS compatible outputs IISupply voltage of 3.3V 10% II25MHz crystal or clock input frequency The PI6C557-03AQ provides two differential (HCSL) or LVDS spread spectrum outputs. The PI6C557-03AQ is configured to select spread and clock selection. Using Pericom's patented PhaseLocked Loop (PLL) techniques, the device takes a 25MHz crystal input and produces two pairs of differential outputs (HCSL) at 25MHz, 100MHz, 125MHz and 200MHz clock frequencies. It also provides spread selection of -0.5%, -0.75%, and no spread. IIHCSL outputs, 0.8V Current mode differential pair IIJitter 35ps cycle-to-cycle (typ) IISpread of -0.5%, -0.75%, and no spread IIAEC-Q100 qualified IISpread Bypass option available IISpread and frequency selection via external pins IIPackaging: (Pb-free and Green) aa 16-pin TSSOP (L16) Pin Configuration (16-Pin TSSOP) Block Diagram VDD 2 SS1:SS0 S1:S0 2 Control Logic 1 16 VDDX S1 2 15 CLK0 SS0 3 14 CLK0 X1/CLK 4 13 GNDA X2 5 12 VDDA OE 6 11 CLK1 GNDX 7 10 CLK1 SS1 8 9 IREF CLK1 X1/CLK Pulling Capacitors S0 CLK0 Phase Lock Loop 2 25 MHz crystal or clock X2 CLK0 CLK1 Crystal Driver 2 GND All trademarks are property of their respective owners. RR OE 14-0076 1 www.pericom.com PI6C557-03AQ Rev A 05/22/14 PI6C557-03AQ PCIe 2.0 Clock Generator with 2 HCSL Outputs for Automotive Applications Pin Description Pin # Pin Name I/O Type Description 1 S0 Input Select pin 0 (Internal pull-up resistor). See Table 1. 2 S1 Input Select pin 1 (Internal pull-up resistor). See Table 1. 3 SS0 Input Spread Select pin 0 (Internal pull-up resistor). See Table 2. 4 X1/CLK Input Crystal or clock input. Connect to a 25MHz crystal or single ended clock. 5 X2 Output Crystal connection. Leave unconnected for clock input. 6 OE Input Output enable. Internal pull-up resistor. 7 GNDX Power Crystal ground pin. 8 SS1 Input Spread Select pin 1 (Internal pull-up resistor). See Table 2. 9 IREF Output Precision resistor attached to this pin is connected to the internal current reference. 10 CLK1 Output HCSL compliment clock output 11 CLK1 Output HCSL clock output 12 VDDA Power Connect to a +3.3V source. 13 GNDA Power Output and analog circuit ground. 14 CLK0 Output HCSL compliment clock output 15 CLK0 Output HCSL clock output 16 VDDX Power Connect to a +3.3V source. Table 2: Spread Selection Table Table 1: Output Select Table S1 S0 CLK(MHz) SS1 SS0 Spread 0 0 25 0 0 No Spread 0 1 100 0 1 Down -0.5 1 0 125 1 0 Down -0.75 1 1 200 1 1 No Spread All trademarks are property of their respective owners. 14-0076 2 www.pericom.com PI6C557-03AQ Rev A 05/22/14 PI6C557-03AQ PCIe 2.0 Clock Generator with 2 HCSL Outputs for Automotive Applications Application Information Output Structures Decoupling Capacitors Decoupling capacitors of 0.01F should be connected between each VDD pin and the ground plane and placed as close to the VDD pin as possible. IREF =2.3mA 6*IREF Crystal Use a 25MHz fundamental mode parallel resonant crystal with less than 300PPM of error across temperature. Crystal Capacitors CL = Crystals's load capacitance in pF Crystal Capacitors (pF) = (CL - 8) *2 R R=475 For example, for a crystal with 16pF load caps, the external effective crystal cap would be 16 pF. (16-8)*2=16. See Output Termination Sections Current Source (IREF) Reference Resistor - R R If board target trace impedance is 50, then R R = 475 providing an IREF of 2.32 mA. The output current (IOH) is 6*IREF. Output Termination The PCI Express differential clock outputs of the PI6C557-03AQ are open source drivers and require an external series resistor and a resistor to ground. These resistor values and their allowable locations are shown in detail in the PCI Express Layout Guidelines section. The PI6C557-03AQ can be configured for LVDS compatible voltage levels. See the LVDS Compatible Layout Guidelines section. All trademarks are property of their respective owners. 14-0076 3 www.pericom.com PI6C557-03AQ Rev A 05/22/14 PI6C557-03AQ PCIe 2.0 Clock Generator with 2 HCSL Outputs for Automotive Applications PCI Express Layout Guidelines Common Recommendations for Differential Routing Dimension or Value Unit L1 length, route as non-coupled 50 trace. 0.5 max inch L2 length, route as non-coupled 50 trace. 0.2 max inch L3 length, route as non-coupled 50 trace. 0.2 max inch RS 33 RT 49.9 Differential Routing on a Single PCB Dimension or Value Unit L4 length, route as coupled microstrip 100 differential trace. 2 min to 16 max inch L4 length, route as coupled stripline 100 differential trace. 1.8 min to 14.4 max inch Differential Routing to a PCI Express connector Dimension or Value Unit L4 length, route as coupled microstrip 100 differential trace. 0.25 min to 14 max inch L4 length, route as coupled stripline 100 differential trace. 0.225 min to 12.6 max inch PCI Express Device Routing L1 L2 RS L1' L4 L4' L2' RS RT PI6C557-03AQ Output Clock L3' RT PCI-Express Load or Connector L3 Typical PCI Express (HCSL) Waveform 800 mV 0 250 ps tOR 400 ps 0.52 V 0.175 V All trademarks are property of their respective owners. 14-0076 tOF 0.52 V 0.175 V 4 www.pericom.com PI6C557-03AQ Rev A 05/22/14 PI6C557-03AQ PCIe 2.0 Clock Generator with 2 HCSL Outputs for Automotive Applications Application Information LVDS Recommendations for Differential Routing Dimension or Value Unit L1 length, route as non-coupled 50 trace. 0.5 max inch L2 length, route as non-coupled 50 trace. 0.2 max inch RP 100 RQ 100 RT 150 L3 length, route as 100 differential trace. L3 length, route as 100 differential trace. LVDS Device Routing L1 L3 RQ L3' L1' RT PI6C557-03AQ Clock Output All trademarks are property of their respective owners. RT L2' 14-0076 RP LVDS Device Load L2 5 www.pericom.com PI6C557-03AQ Rev A 05/22/14 PI6C557-03AQ PCIe 2.0 Clock Generator with 2 HCSL Outputs for Automotive Applications Maximum Ratings (Above which useful life may be impaired. For user guidelines, not tested.) Supply Voltage to Ground Potential . . . . . . . . . . . . . . . . . . . . . . . 5.5V All Inputs and Outputs . . . . . . . . . . . . . . . . . . . . . -0.5V to VDD+0.5V Ambient Operating Temperature . . . . . . . . . . . . . . . . . . . -40 to +85C Storage Temperature . . . . . . . . . . . . . . . . . . . . . . . . . . . . -65 to +150C Junction Temperature . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 150C Soldering Temperature . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 260C Note: Stresses greater than those listed under MAXIMUM RATINGS may cause permanent damage to the device. This is a stress rating only and functional operation of the device at these or any other conditions above those indicated in the operational sections of this specification is not implied. Exposure to absolute maximum rating conditions for extended periods may affect reliability. EDS Protection (Input) . . . . . . . . . . . . . . . . . . . . . 2000 V min (HBM) Electrical Specifications Recommended Operation Conditions Parameter Min. Ambient Operating Temperature Power Supply Voltage (measured in respect to GND) Typ. Max. Unit -40 +85 C +3.0 +3.6 V DC Characteristics (VDD = 3.3V 10%, TA = -40C to +85C) Symbol Parameter VDD Supply Voltage Voltage(1) VIH Input High VIL Input Low Voltage(1) IIL Input Leakage Current Conditions Min. Typ. Max. Unit 3.0 3.3 3.6 V OE 2.0 VDD +0.3 V OE GND -0.3 0.8 V -20 20 0 < Vin < VDD With input pull-up and pull-downs A Without input pull-up -5 and pull-downs 5 R L = 50, CL = 2pF 95 mA IDDOE Operating Supply Current OE = LOW 50 mA CIN Input Capacitance @ 55MHz 7 pF COUT Output Capacitance @ 55MHz 6 pF LPIN Pin Inductance 5 nH ROUT Output Resistance IDD CLK Outputs 3.0 k Notes: 1. Single edge is monotonic when transitioning through region. All trademarks are property of their respective owners. 14-0076 6 www.pericom.com PI6C557-03AQ Rev A 05/22/14 PI6C557-03AQ PCIe 2.0 Clock Generator with 2 HCSL Outputs for Automotive Applications HCSL Output AC Characteristics (VDD = 3.3V 10%, TA = -40C to +85C) Symbol Parameter Conditions Min. Typ. Max. FIN Input Frequency VOUT Output Frequency VOH Output High Voltage (1,2) VOL Output Low Voltage(1,2) VCPA Crossing Point Voltage(1,2) Absolute VCN Crossing Point Voltage Variation over all edges JCC Jitter, Cycle-to-Cycle(1,3) JRMS PCIe RMS Jitter PCIe 2.0 Test Method @ 100MHz Output MF Modulation Frequency Spread Spectrum 30 tOR Rise Time From 0.175V to 0.525V tOF Fall Time(1,2) From 0.525V to 0.175V TSKEW Skew between outputs At Crossing Point Voltage TDUTY-CYCLE Duty Cycle(1,3) TOE Output Enable Time(5) TOT Output Disable Time tSTABLE From power-up to VDD =3.3V From Power-up VDD =3.3V 3.0 ms tSPREAD Setting period after spread change Setting period after spread change 3.0 ms 25 MHz 25 100 MHz HCSL output @ VDD = 3.3V (1,2,4) 660 800 -150 0 250 350 MHz 900 mV 550 mV 140 mV 60 ps 3.1 ps 33 kHz 175 500 ps 175 500 ps 50 ps 55 % All outputs 10 s All outputs 10 s 31.5 45 (5) 200 mV 35 (1,2) Unit Notes: 1. RL = 50-Ohm with CL = 2 pF 2. Single-ended waveform 3. Differential waveform 4. Measured at the crossing point 5. CLK pins are tri-stated when OE is LOW Thermal Characteristics Symbol Parameter Conditions JA Thermal Resistance Junction to Ambient Still air JC Thermal Resistance Junction to Case All trademarks are property of their respective owners. 14-0076 7 Min. www.pericom.com Typ. PI6C557-03AQ Max. Unit 90 C/W 24 C/W Rev A 05/22/14 PI6C557-03AQ PCIe 2.0 Clock Generator with 2 HCSL Outputs for Automotive Applications Recomended Crystal Specification Pericom recommends: a) FL2500184Q, SMD 3.2x2.5(4P), 25M, CL=20pF, Frequency Tolerance 15ppm, Stability 20ppm (http://www.pericom.com/pdf/datasheets/se/FL.pdfb) Recommended Crystal Circuit The following diagram shows PI6C557-03AQ crystal circuit connection with a parallel crystal. For the C L=20pF parallel crystal, it is suggested to use C1=27 pF, C2=27 pF in general. C1 and C2 can be adjusted to fine tune to the target ppm of crystal oscillation according to different board layouts. R1=360 ohm is recommended in layout for smaller size crystal drive level adjustment. Xin C1 27pF 25M Crystal (CL=20pF) Optional 360 Xout C2 27pF All trademarks are property of their respective owners. 14-0076 8 www.pericom.com PI6C557-03AQ Rev A 05/22/14 PI6C557-03AQ PCIe 2.0 Clock Generator with 2 HCSL Outputs for Automotive Applications Packaging Mechanical: 16-Pin TSSOP (L) Note: For latest package info, please check: http://www.pericom.com/products/packaging/mechanicals.php Ordering Information Ordering Code Package Code Package Type PI6C557-03AQLE L Pb-free & Green, 16-pin TSSOP Notes: * Thermal characteristics can be found on the company web site at www.pericom.com/packaging/ * "E" denotes Pb-free and Green * Adding an "X" at the end of the ordering code denotes tape and reel packaging All trademarks are property of their respective owners. 14-0076 9 www.pericom.com PI6C557-03AQ Rev A 05/22/14