LMK03002C Precision Clock Conditioner with Integrated VCO Evaluation Board Operating Instructions 7-23-2007 National Semiconductor Corporation Interface 2900 Semiconductor Dr.
L M K 0 3 0 0 2 C E V A L U A T I O N B O A R D O P E R A T I N G I N S T R U C T I O N S TABLE OF CONTENTS GENERAL DESCRIPTION ............................................................................................................................... 3 LOOP FILTER #1 ........................................................................................................................................... 3 READ FIRST, BASIC OPERATION ................................................................
L M K 0 3 0 0 2 C E V A L U A T I O N B O A R D O P E R A T I N G I N S T R U C T I O N S General Description The LMK03002C Evaluation Board simplifies evaluation of the LMK03002C Precision Clock Conditioner with Integrated VCO. The package consists of an evaluation board and CodeLoader software. The CodeLoader software will run on a Windows 2000 or Windows XP PC. The purpose of the CodeLoader software is to program the internal registers of the LMK03002C device through a TM MICROWIRE interface.
L M K 0 3 0 0 2 C E V A L U A T I O N B O A R D O P E R A T I N G I N S T R U C T I O N S Read first, Basic Operation Read the document, “Installing CodeLoader 4 & USB Driver” for instructions to prepare the computer for usage with the evaluation board before continuing with the hardware setup. For basic operation… 1. Connect a low noise 3.3 V power supply to the Vcc connector located at the top left of the board 2. Connect the CodeLoader cable to the uWire header located in the lower left.
L M K 0 3 0 0 2 C E V A L U A T I O N B O A R D O P E R A T I N G I N S T R U C T I O N S Read first, Basic Operation (Continued) 3. Connect… • PC directly to the evaluation board with the LPT to uWire cable, plugging the cable into an LPT port on the computer and then the 10 pin ribbon connector to the evaluation board. This setup is shown below. The cable can be removed after programming to minimize noise and EMI.
L M K 0 3 0 0 2 C E V A L U A T I O N B O A R D O P E R A T I N G I N S T R U C T I O N S Read first, Basic Operation (Continued) 4. Start CodeLoader 4. 5. Select the USB or LPT Communication Mode on the Port Setup tab as appropriate. 6.
L M K 0 3 0 0 2 C E V A L U A T I O N B O A R D O P E R A T I N G I N S T R U C T I O N S Read first, Basic Operation (Continued) 7. Enable output to be measured, any of CLKout(0-7) or EN_Fout from either Clock Outputs or Bits/Pins tab. 8. Program the part by clicking “Keyboard Controls” “Load Device” or by pressing Ctrl+L. 9. Make measurements… After programming, the uWire cable can be unplugged from the evaluation board to minimize noise and EMI.
L M K 0 3 0 0 2 C E V A L U A T I O N B O A R D O P E R A T I N G I N S T R U C T I O N S Board Information OSCin By default the board is configured to use the on-board crystal oscillator. It is also possible to use the board with a single ended or differential reference source at the OSCin port. Below are several possible configurations for driving OSCin.
L M K 0 3 0 0 2 C E V A L U A T I O N B O A R D O P E R A T I N G I N S T R U C T I O N S Features of the board • • • • • • • • Either one of two loop filters can be selected by shorting either R22 or R5. More info about each loop filter can be found in the General Description and Appendix A. Test points for each of the uWire lines are scattered in the lower left corner of the board and include: GOE_TP, DATAuWire, CLKuWire, LEuWire, SYNC_TP, and LD_TP.
L M K 0 3 0 0 2 C E V A L U A T I O N B O A R D O P E R A T I N G I N S T R U C T I O N S Recommended Equipment Power Supply The Power Supply should be a low noise power supply. An Agilent 6623A Triple power supply with LC filters on the output to reduce noise was used in creating these evaluation board instructions. Phase Noise / Spectrum Analyzer For measuring phase noise an Agilent E5052A is recommended.
Below ~1 kHz phase noise is dominated by the crystal 10 Hz – 20 MHz integrated RMS jitter = 474 fs 100 Hz – 20 MHz integrated RMS jitter = 202 fs 12 kHz – 20 MHz integrated RMS jitter = 188 fs (shown) O P E R A T I N G Below ~1 kHz phase noise is dominated by the crystal 10 Hz – 20 MHz integrated RMS jitter = 636 fs 100 Hz – 20 MHz integrated RMS jitter = 205 fs 12 kHz – 20 MHz integrated RMS jitter = 193 fs (shown) B O A R D Reference source is on board 16 MHz crystal Output Frequency = 1632 MHz In
L M K 0 3 0 0 2 C E V A L U A T I O N B O A R D O P E R A T I N G I N S T R U C T I O N S Delays These delay measurements illustrate how skew errors due to different length traces may be tuned out. The delay may be adjusted in steps of 150 ps.
L M K 0 3 0 0 2 C E V A L U A T I O N B O A R D O P E R A T I N G I N S T R U C T I O N S CodeLoader Settings The Port Setup tab tells CodeLoader what signals are assigned to which pins. If this is wrong, the part will not program. Part setup can be restored to the default state by clicking Mode “16 MHz OSCin” The default reference oscillator used for these instructions is 16 MHz and the restored mode expects a 16 MHz OSCin signal.
L M K 0 3 0 0 2 C E V A L U A T I O N B O A R D O P E R A T I N G I N S T R U C T I O N S The Bits/Pins tab shows some of the internal registers which are not accessible from any of the other visual tabs like “PLL” and “Clock Outputs.” Right click on any of the bits for description. Program Bits POWERDOWN EN_Fout OSCin_FREQ PLL_MUX DIV4 RESET VCO_R3_LF VCO_R4_LF VCO_C3_C4_LF EN_CLKout0..3 EN_CLKout_Global Powers the part down. Turns on the Fout pin for measuring the internal VCO.
L M K 0 3 0 0 2 C E V A L U A T I O N B O A R D O P E R A T I N G I N S T R U C T I O N S The Registers tab shows the raw bits which will be programmed when device is loaded by clicking Keyboard Controls Load Device or Ctrl+L. The Clock Outputs tab allows the user to visualize the clock distribution portions of the device. From this tab the device’s dividers, delays, clock output muxes, and output drivers can be programmed along with internal loop filter values.
L M K 0 3 0 0 2 C E V A L U A T I O N B O A R D O P E R A T I N G I N S T R U C T I O N S The PLL tab shows a conventional PLL diagram along with the VCO Divider. It is important to realize that the total effective N value is PLL N Counter * VCO Divider. This means that the “channel spacing” is the Phase Detector Frequency * VCO Divider. Depending on the situation, this may require the R Counter multiplied up by the value of the VCO Divider to achieve desired VCO output frequencies.
L M K 0 3 0 0 2 C E V A L U A T I O N B O A R D O P E R A T I N G I N S T R U C T I O N S Appendix A: VCO Performance The internal VCO performance is measured by using a narrow bandwidth loop filter. By default the narrow loop bandwidth filter is stuffed as Loop Filter #2 in positions C1_AUX, C2_AUX, C2p_AUX, and R2_AUX and has a loop bandwidth of 55 Hz. See the Loop Filter section in Board Options for more detail about switching between the two different loop filters.
L M K 0 3 0 0 2 C E V A L U A T I O N B O A R D O P E R A T I N G I N S T R U C T I O N S VCO Phase Noise – Narrow Loop Bandwidth This plot shows the noise of the VCO at 1632 MHz using a 500 kHz Phase Detector Frequency. An external oscillator was used for this plot, since the VCO noise dominates, reference oscillator noise is not critical. The loop bandwidth has been minimized so that the VCO is the dominant noise contributor. 10 Hz – 20 MHz integrated RMS jitter = 107.
L M K 0 3 0 0 2 C E V A L U A T I O N B O A R D O P E R A T I N G I N S T R U C T I O N S Appendix B: Impact of Reference on Phase Noise Inside the loop bandwidth of a PLL the phase noise is set by the quality of the reference oscillator used. For this reason it is important to select a reference oscillator suitable for the application.
L M K 0 3 0 0 2 C E V A L U A T I O N B O A R D O P E R A T I N G I N S T R U C T I O N S Appendix C: Schematics LMK0300x - Main Board LMK0300x - Main Board.sch LMK0300x - Outputs LMK0300x - Outputs.
L M K 0 3 0 0 2 C E V A L U A T I O N B O A R D O P E R A T I N G I N S T R U C T I O N S R109 SMA TCXO_RF Vin R3 Vcc 0 ohm Vcc R110 Open 0 ohm Vcc OSCin R111 Open C3 Open R14 Open R11 0 ohm GND Vcc B1 1 2 3 R10 Open R12 0 ohm 6 5 4 Sd S-ct S R17 Open 0 ohm Osc1 C9 0.1 uF Y1 0.
L M K 0 3 0 0 2 C Vcc E V A L U A T I O N Vcc Vcc CLKout0 R35 Open I N S T R U C T I O N S Vcc Vcc CLKout2 R40 Open C52 CLKout0 OpenSMA PC1 PC2 B3 C53 CLKout0* SMA CLKout0* 0.1 uF PC3 PC4 C55 0.1 uF C57 R36 Open R38 Open R39 Open Open 6 5 4 Sd S-ct S P Pd 1 R87 0 ohm 3 ADT2-1T GND CLKout2* CLKout2* SMA GND 0.1 uF R34 Open R107 R51 Open PC5 CLKout1* OpenSMA CLKout1* CLKout2 OpenSMA CLKout2 R44 Open 0.
L M K 0 3 0 0 2 C E V A L U A T I O N B O A R D O P E R A T I N G I N S T R U C T I O N S Appendix D: Bill of Materials Part Capacitors 47 pF Manufacturer Part Number Qnt Kemet C0603C470J5GAC 1 100 pF 100 pF 12 nF Kemet Kemet Kemet C0402C101J5GAC C0603C101J5GAC C0603C123K1RACTU 14 1 1 0.1 uF Kemet C0603C104J3RAC 16 0.
L M K 0 3 0 0 2 C 15 k 27 k E V A L U A T I O N B O A R D O P E R A T I N G I N S T R U C T I O N S Vishay Vishay CRCW0603153JRT1 CRCW0603273JRT1 4 3 R88, R89, R90, R91 R83, R84, R85 LMK0300xC OSC - CRYSTEK 33xx ADT2-1T National Semiconductor Crystek Minicircuits LMK03002CI C3391-16.000 ADT2-1T 1 1 1 SMA 3.3 V zener Johnson Components Comchip 11 2 PCB_LMK0300x HEADER_2X5(POLARIZED) SPCS-8 Printed Circuits Corp FCI Electronics SPC Technology 142-0701-851 CZRU52C3V3 PCB_LMK0300x rev 1.
L M K 0 3 0 0 2 C E V A L U A T I O N B O A R D O P E R A T I N G Appendix E: Build Diagram 25 I N S T R U C T I O N S
L M K 0 3 0 0 2 C E V A L U A T I O N B O A R D O P E R A T I N G I N S T R U C T I O N S Bottom Build Diagram 26
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