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      • Si522xx Si52212 Si52208 Si52204 Si52202 FAQ

        tihopkin | 09/255/2017 | 07:03 PM

        General Questions

        1. Where can I find datasheets and user guides for Si522xx?

        Datasheet: https://www.silabs.com/documents/public/data-sheets/si522xx-datasheet.pdf

         

        Si52204 Evaluation Kit (EVB): https://www.silabs.com/products/development-tools/timing/clock/si52204-evb-evaluation-kit

         

        EVB User Guide: https://www.silabs.com/documents/public/user-guides/ug277-si52204-evb.pdf

         

        Some Helpful Application Notes

        Description of the new PCI Express 4.0 Jitter Requirements:

        https://www.silabs.com/documents/public/application-notes/an946-pci-express-jitter-requirements.pdf

         

        Help on converting HCSL Signals to either LVPECL, LVDS, or CML:

        https://www.silabs.com/documents/public/application-notes/an781-alternative-output-termination.pdf

         

        Tips for driving longer PCI Express clock lines:

        https://www.silabs.com/documents/public/application-notes/an871-driving-long-pcie-clock-lines.pdf

         

        1. Where can I find more information regarding the Si522xx's PCIe performance?

        Try looking in our PCI Express Learning Center: https://www.silabs.com/products/timing/pci-express-learning-center

         

        There you can download our PCIE Express Clock Jitter Tool and see sample data files from the Si52204.

         

        1. Where can I find quality and reliability documents for Si522xx?

        Try our RFI Portal: https://ops.silabs.com/wrfi/pages/PartSearch

         

        If you aren’t able to find the needed documents there, try emailing our quality team at:  DL.RFISupport@silabs.com

         

        1. Want sample parts?

        We are currently giving out samples for Si52202-A01, Si52204-A01, Si52208-A01, and Si52212-A01. To request one, select the sample option beneath the desired part number in our PCIe Clock Generator Product Matrix.

        https://www.silabs.com/products/timing/clocks/pcie-clock-generators

         

        Part Specific Questions

        Si52202

        1. What is the I2C address for Si52202?

        Since Si52202 does not have a REF/SA pin to select the I2C address, the address will always be set to 0x6A.

      • What is Lead Finish for Si5338, Si5335, or Si5330?

        Jitterati | 07/192/2017 | 11:17 AM

        Lead/Terminal Finish details for all Si5338/Si5335/Si5330 family of devices:

         

        Ni : 10 u'' ( Min ) 
        Pd : " 0.1 u'' ( Min ) 
        Ag- Au alloy : 0.2 u'' ( Min ) Silver content is very low. 

        If you require more detail on lead finish, please work through your Silicon Labs sales rep to submit a RFI (Request For Information) with the details of the additional information you need. 

      • Si5348 FAQ

        kgsmith | 06/174/2017 | 04:23 AM

        Please see the attached document for Frequently Asked Questions (FAQ) and their answers regarding the Si5348 Network Synchronizer for SyncE/ 1588 PTP Telecom Boundary (T-BC) and Slave (T-SC) Clocks.

         

        The topics from the Table of Contents are listed below.

         

        PCB Design and Layout Guidance            

        Where can I find the IBIS model for the Si5348?

        Where can I find the Si5348 schematic footprints and symbols? 

        Where can I find the package and PCB footprint information?    

        Do you have layout recommendations I should follow? 

        Do you have a list of recommended crystals?     

        I don’t want to use a crystal with the Si5348. Can I use an XO or TCXO as the XA/XB reference instead?  And if so, how do I interface an external oscillator to the device?

        Why do I need both an OCXO or TCXO and a crystal?      

        What are the recommended bandwidths and why?       

        Are there any power supply filtering requirements or recommendations?           

        Is there any specific power supply sequencing requirement?     

        What serial interfaces does the device support?              

        How do I properly terminate input and output clocks?   

        Where can I get detailed material composition information on these devices?   

        Is the part RoHS compliant?       

        What is the Moisture Sensitivity Level (MSL) rating for the Si5348?          

        What is the recommend profile for solder reflow process?          

        Frequency Plan and Clock Design Decisions       

        What development software/tools do you have available to use with the Si5348?            

        Where can I find ClockBuilder Pro Documentation?         

        How do I select proper jitter attenuation bandwidth?    

        Is there a recommended full device programming procedure?  

        Do I need to update any divider if I write Soft_Rst_All? 

        What input buffer should I select?          

        How can I do DCO mode?            

        Do I have to provide an input clock in DCO mode?           

        How do I calculate a frequency plan without CBPro?       

        Does the Si5348 support Zero-Delay Buffer operation? 

        Can I change an output frequency on the fly?    

        Does the Si5348 support 1Hz input clocks?           

        Is there support for output frequencies down to 1Hz?  

        Does the device support automatic input clock selection and does it support hitless switching? 

        Can I do automatic switching on IN3 and IN4?    

        Is LOS supported on the CMOS IN3 and IN4?      

        Is OOF supported on the CMOS IN3 and IN4?    

        Can I use IN3 or IN4 on DSPLL C or A?     

        Can the Si5348 be used as a Grandmaster, Boundary Clock or Slave Clock?           

        How do I know the output drift MTIE and TDEV

        When should frequency ramp be enabled?        

      • Si5347/46 FAQ

        kgsmith | 06/174/2017 | 04:19 AM

        Please see the attached document for Frequently Asked Questions (FAQ) and their answers regarding the Si5347 and Si5346 Quad and Dual DSPLL Any-Frequency, Any-Output Jitter Attenuators.

         

        The topics from the Table of Contents are listed below.

         

        PCB Design and Layout Guidance

        Where can I find the IBIS model for the Si5347/46?

        Where can I find the Si5347/46 schematic footprints and symbols?

        Where can I find the package and PCB footprint information?

        Do you have layout recommendations I should follow?

        Do you have a list of recommended crystals?

        I don’t want to use a crystal with the Si5347/46.  Can I use an XO or TCXO as the XA/XB reference instead?  And if so, how do I interface an external oscillator to the device?

        Are there any power supply filtering requirements or recommendations?

        Is there any specific power supply sequencing requirement?

        What serial interfaces does the device support?

        How do I properly terminate input and output clocks?

        Where can I get detailed material composition information on these devices?

        Is the part RoHS compliant?

        What is the Moisture Sensitivity Level (MSL) rating for the Si5347/46?

        What is the recommend profile for solder reflow process?

        Frequency Plan and Clock Design Decisions

        What development software/tools do you have available to use with the Si5347/46?

        Where can I find ClockBuilder Pro Documentation?

        How do I select proper jitter attenuation bandwidth?

        Does the device support automatic input clock selection and does it support hitless switching?

        Is there a recommended full device programming procedure?

        Can I change one output frequency without disturbing other output(s)?

        Do I need to write pre-amble/post-amble for Frequency-On-The-Fly?

        Should I use Soft_Reset_All or Soft_Reset_DSPLLx for Frequency-On-The-Fly?

        Do I need to update any divider if I strobe Soft_Reset_All?

        How do I do DCO mode?

        Do I have to provide an input clock in DCO mode?

        How do I calculate a frequency plan without CBPro?

        Does the Si5347/46 support Zero-Delay Buffer operation?

         
      • Si5345/44/42 FAQ

        kgsmith | 06/174/2017 | 04:15 AM

        Please see the attached document for Frequently Asked Questions (FAQ) and their answers regarding the Si5345, Si5344, and Si5342 10-Channel, 4-Channel, and 2-Channel Any-Frequency, Any-Output Jitter Attenuator/Clock Multipliers.

         

        The topics from the Table of Contents are listed below.

         

        PCB Design Considerations

        Where should I look for schematic design assistance?

        Where should I look for layout recommendations?

        Where can I find the package and PCB footprint information?

        Which ordering part number (OPN) is right for me?

        Where can I find Si5345/44/42 layout footprints and schematic symbols?

        Where can I find the IBIS model for the Si5345/44/42?

        What reference clock should be used on the XA/XB input?

        What serial interfaces does the device support?

        Are there any power supply filtering requirements or recommendations?

        How do I properly terminate input and output clocks?

        Where can I get detailed material composition information on these devices?

        Is the part RoHS compliant, REACH compliant and lead (Pb) free?

        What is the Moisture Sensitivity Level (MSL) rating for the SI5345/44/42?

        What is the recommended profiled for solder reflow process?

        Frequency Plan and Clock Design Considerations

        What development software do you have available to use with Si5345/44/42?

        Where can I find ClockBuilder Pro Documentation?

        Is there a recommended full device programming procedure?

        What input buffer should I select?

        Does the device support automatic input clock selection hitless switching?

        How do I select proper jitter attenuation bandwidth?

        Can I change an output frequency on the fly?

        What is the best way to configure output clocks to optimize jitter performance?

        Where can I look for help with DCO mode?

        How much power will my frequency plan draw?

        How can I know the performance of my frequency plan if I can’t measure phase noise or jitter?

        Does the Si5345/44/42 support Zero-Delay Buffer operation?

        Common Debug Questions

        The device is not generating output clocks, what can I do?

        I am unable to establish communication with the device via the serial interface, what can I do? 

         
         
      • Si5380 FAQ

        Nari | 06/174/2017 | 04:12 AM

        Please see the attached document for Frequently Asked Questions (FAQ) and their answers regarding the Si5380 Ultra-Low Phase Noise, 12-output JESD204B Clock Generator.

         

        The topics from the Table of Contents are listed below.

         

        Frequency Plan and Clock Design Decisions

        What is the output frequency range of the Si5380?

        What output frequency restrictions does the Si5380 have?

        What development software/tools do you have available to use with the Si5380?

        Are there any restriction on output clock placement?

        How do I select proper jitter attenuation bandwidth?

        Does the device support automatic input clock selection and does it support hitless switching?

        Is there a recommended full device programming procedure?

        Can I change device settings in my system at runtime?

        Can I change between several different frequency plans without fully re-configuring the device?

        Can I change one output frequency without disturbing other output(s)?

        Does the Si5380 support JESD204B operation?

        How much power will my frequency plan draw?

        I need to know the phase noise of my frequency plan, but am not able to make these measurements.

        I need more than 12 outputs, what can I do?

        Does the Si5380 support Zero-Delay Buffer operation?

        PCB Design and Layout Guidance

        Where can I find the package and PCB footprint information?

        Do you have layout recommendations I should follow?

        Do I need to put thermal vias under the E-pad of the device in my PCB layout?

        Do you have a list of items to check during the schematic review?

        Where can I find the IBIS model for the Si5380?

        Where can I find the Si5380 schematic footprints and symbols?

        What frequency options are available for the XA/XB connections?

        I don’t want to use a crystal with the Si5380. Can I use an XO or TCXO as the XA/XB reference instead? And if so, how do I interface an external oscillator to the device?

        Are there any power supply filtering requirements or recommendations?

        Is there any specific power supply sequencing requirement?

        What serial interfaces does the device support?

        Where can I get detailed material composition information on these devices?

        Is the part RoHS compliant?

        What is the Moisture Sensitivity Level (MSL) rating for the Si5380?

        What is the recommend profile for solder reflow process? 

         
      • CBProgrammer CBPro-DONGLE FAQ

        tihopkin | 06/173/2017 | 04:26 PM
        • I burned a project file to my device with a new Base I2C address, but the base address in the device was not changed after the burn process was complete (non-firmware based devices).

        The I2C address will not be changed during the burn process. Changes to the base I2C address in the CBPro Configuration Wizard will be included in exports and the project file used to create orderable part numbers. However, this change is not burned to the device using the NVM Burn Tool. The image below shows this message in CBPro. 

             I2C_Address_Message.bmp
        To permanently change the I2C base address on your device, you need to use the I2C Address Burn Tool. See the images below to use the tool.


             start_I2c_tool.jpg  run_tool.jpg

         

        • Why can’t I communicate with the Si534x8x device on my hardware using the CBPro Dongle?

        General Steps to Resolve a Communication Issue (Non-Firmware based devices)
        1. Verify which communication protocol your hardware is using – SPI or I2C.
        2. Verify the voltage level on the I2C_SEL control pin on the DUT. This level should be logic low (0 V) if your communication protocol is SPI. This level should be logic high (1.8 V or 3.3 V – refer step 3 below) if your communication protocol is I2C.
        3. Verify the value of the IO_VDD_SEL bit (Register 0x0943[0]) for the DUT. If IO_VDD_SEL is 0, the I/O Voltage setting should be 1.8V. If IO_VDD_SEL is 1, the I/O Voltage setting should 3.3V. If you do not know this value, you can try both voltages to determine
        which voltage level will work successfully.
        4. If the communication protocol is I2C, verify the I2C address setting (Register 0x000B) for the device. You may also need to verify
        the voltage level on the A0/CSb and A1/SDO pins if they are not connected to the field programmer. The level on these pins set bit 1 and bit 0 in the I2C address. If these are connected to the CBPro Dongle, they are both driven low.  For more information on this issue refer to section 7.1 in UG286: ClockBuilderPro Field Programmer Kit


        General Steps to Resolve a Communication Issue (Firmware based devices)
        1. Verify the I2C address for the device.
        2. Verify the voltage level on the A0/CSb and A1/SDO pins if they are not connected to the field programmer. The level on these pins set bit1 and bit 0 in the I2C address. If these are connected to the CBPro Dongle, they are both driven low. For more information on this issue refer to section 7.1 in UG286: ClockBuilderPro Field Programmer Kit

         

        • Why do I have a communication error when I write my new project to the device?

        Does the new plan change the IO_VDD_SEL Bit (Register 0x0943[0]) value? In order for the CBPro Dongle to communicate with the device correctly, the dongle’s IO voltage needs to match the IO_VDD_SEL bit in the device. If the plan changes this bit during the writing process, communication will fail. To determine if the new plan is changing this bit, perform the following steps:
        • Read the current value in the device by using the DUT Register Editor tab in the EVB GUI window.
        • Determine if the new plan changes the value. This can be done by looking at the Host Interface tab in the Design Dashboard of the new project.
        • If VDD (Core) radio button selected and 0x943 = 0, no change from new plan,
        Else VDD (Core) radio button selected and 0x943 = 1, new plan is changing IO_VDD_SEL refer to Section 7.3 in document UG286: ClockBuilderPro Field Programmer Kit.
        • If VDDA (3.3V) radio button selected and 0x943 = 1, no change from new plan,
        Else VDDA (3.3V) radio button selected and 0x943 = 0, new plan is changing IO_VDD_SEL refer to Section 7.3 in document UG286: ClockBuilderPro Field Programmer Kit.
        The following window shows how to read the IO_VDD_SEL bit from the device and check the project Host Interface setting.
         

        EVB-GUI-943.jpg

        Host-Interface.jpg

         

        • Can I use my I2C master to communicate with the device on a Silicon Labs Evaluation Board?

        You can communicate with the DUT using I2C, but there are a few steps and issues that need to be considered:

        - You will need to connect your I2C master to the evaluation board. This can be done using J17 for the Si5340, Si5342, Si5344, and Si5346 boards. This can be done using J36 for the Si5341, Si5345, Si5347, Si5348, Si5380, Si5381, and Si5382 boards. Remove the jumpers J17 or J36 and connect your I2C master to the pins labeled SDA, SCLk, and GND. You may also want to drive the pins labaled A0 and A1 low to use the base I2C address of the device.

        - Remove the jumper labeled "I2C_SEL" to allow this signal to be pulled high which puts the device in I2C mode. Do not run ClockBuilder Pro while trying to communicate with the device using your I2C master. If ClockBuilder Pro is running, it will override the I2C_SEL jumper and drive this signal low putting the device in SPI mode. If you need to run ClockBuilder to work with the evaluation board before using your I2C master(board regulators, look at register values), exit ClockBuilder Pro and press the button on the board labeled "MCU Reset" before using your I2C master. Pressing the MCU reset button will reset the onboard MCU of the evaluation board and the I2C_SEL will be pulled high putting the device in I2C mode. The MCU reset button will not reset the device or any other settings on the board (it only resets the MCU).

        - Communicate with the device using I2C and the I2C address of the device (base address plus the levels on the A1 and A0 pins of the device. 

         

        • Can I use Field Programmer to communicate with the device on a Silicon Labs Evaluation Board using I2C?

        You can communicate with the DUT using I2C, but there are a few steps and issues that need to be considered:

        - You will need to connect the field programmer to the evaluation board. This can be done using J17 for the Si5340, Si5342, Si5344, and Si5346 boards. This can be done using J36 for the Si5341, Si5345, Si5347, Si5348, Si5380, Si5381, and Si5382 boards. Remove the jumpers on J17 or J36 and connect the Field Programmer to the pins labeled SDA, SCLk, A0, A1, and GND.  

        - Remove the jumper labeled "I2C_SEL" to allow this signal to be pulled high which puts the device in I2C mode.

        - Connect the Field Programmer to a USB port on your computer. You will need to provide power to the evaluation board with either a powered USB hub not connected to your computer or a USB charger that is capable of providing 500 mA of current. If the evaluation board is connected to your computer, you cannot run CBPro. If CBPro detects the evaluation board, it will drive the I2C_SEL pin low putting the device in SPI mode.

        Note**: If you need to control functionality on the evaluation board, such as enabling output regulators, you connect the evalution board to your computer through a powered usb hub and perform the following steps:

        1. Open CBPro and setup the evaluation board (e.g. enable output regulators)
        2. Disconnect the hub from your PC 
        • Do not disconnect power from the hub
        • Do not disconnect the evaluation board from the hub
        1. Press the button on the evaluation board labeled "MCU RST"
        • This only resets the MCU on the evaluation board. The Si538x4x device is not reset.
        1. Confirm the jumper labeled "I2C_SEL" is not installed

        With the field programmer connected to your computer and the evalution board powered with another source, start CBPro and setup the field programmer for I2C communication.