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AD9530 PLL IS NOT LOCKING

Category: Other
Product Number: AD9530

Hi

Iam using AD9530 in my custom board and evaluating the same.I've programmed the chip and current consumption is as per the datasheet,but not getting any output.

Here Iam attaching the PLL configuration and the register values.Kindly check and suggest why it is not locking.Loop filter values are as per datasheet,and what should be the valus of Cin?

00003c0400053f0114000000000056040000010603040800010001000106011e00001e1e0e0f00050113000000000000";



template
[edited by: lallison at 8:19 PM (GMT -4) on 13 May 2022]
  • Kindly help to resolve this.Awaiting some response

  • Hi,

    sorry for the delay in getting back to you. We always recommend testing the configuration on an evaluation board and then design your own board. 

    If you send me the stp configuration file, I can try to run it on the evaluation board.

    Meanwhile, I recommend:

    - increase the charge pump current to the max 3.2mA

    - verify the loop filter components on LF1, LF2 and LF3 pins used on your board match the one used on the AD9530 evaluation board.

    -leave Cin=55pF the default value

    Petre

  • Thanks for the reply. I dont have an evalboard with me. Also,this device is not there in the ADI Sim CLK simulation tool.

    Will share the stp file of the configuration. Meanwhile could you please verify the register values that iam sending is as per the protocol.

    I have used streaming mode,MSB first and address ascent. Do i have to set IO update as '1'?

    What about VCO calibration settings?

  • I'm not able to upload the stp file here. Could you please share the e-mail id?

  • please add a txt extension in order to upload the stp file

    Thanks

    Petre

  • <header>
    product = AD9530b
    softwareversion = 1.0.0.0
    </header>
    
    <registers>
    Register (Hex),	Value (Hex),	Value (Dec)
    0x0,		0x3C,		60
    0x1,		0x00,		0
    0x2,		0x00,		0
    0x3,		0x00,		0
    0x4,		0x00,		0
    0x5,		0x00,		0
    0x6,		0x00,		0
    0x7,		0x00,		0
    0x8,		0x00,		0
    0x9,		0x00,		0
    0xa,		0x00,		0
    0xb,		0x00,		0
    0xc,		0x56,		86
    0xd,		0x04,		4
    0xe,		0x00,		0
    0xf,		0x00,		0
    0x10,		0x01,		1
    0x11,		0x02,		2
    0x12,		0x03,		3
    0x13,		0x04,		4
    0x14,		0x07,		7
    0x15,		0x26,		38
    0x16,		0x01,		1
    0x17,		0x26,		38
    0x18,		0x01,		1
    0x19,		0x26,		38
    0x1a,		0x15,		21
    0x1b,		0x26,		38
    0x1c,		0x01,		1
    0x1d,		0x0C,		12
    0x1e,		0x00,		0
    0x1f,		0x00,		0
    0x20,		0x16,		22
    0x21,		0x0E,		14
    0x22,		0x0A,		10
    0x23,		0xAF,		175
    0x24,		0x00,		0
    0x25,		0x07,		7
    0x26,		0x01,		1
    0x27,		0x13,		19
    0x28,		0x00,		0
    0x2b,		0x00,		0
    0xfc,		0x00,		0
    0xfd,		0x00,		0
    0xfe,		0x00,		0
    0xff,		0x00,		0
    </registers>
    
    <frefa>
    10000000
    </frefa>
    
    <frefb>
    0
    </frefb>
    
    <header>
    product = AD9530b
    softwareversion = 1.0.0.0
    </header>
    
    <registers>
    Register (Hex),	Value (Hex),	Value (Dec)
    0x0,		0x3C,		60
    0x1,		0x00,		0
    0x2,		0x00,		0
    0x3,		0x05,		5
    0x4,		0x03,		3
    0x5,		0x01,		1
    0x6,		0x00,		0
    0x7,		0x00,		0
    0x8,		0x00,		0
    0x9,		0x00,		0
    0xa,		0x00,		0
    0xb,		0x00,		0
    0xc,		0x56,		86
    0xd,		0x04,		4
    0xe,		0x00,		0
    0xf,		0x00,		0
    0x10,		0x01,		1
    0x11,		0x02,		2
    0x12,		0x03,		3
    0x13,		0x05,		5
    0x14,		0x07,		7
    0x15,		0x26,		38
    0x16,		0x01,		1
    0x17,		0x26,		38
    0x18,		0x01,		1
    0x19,		0x26,		38
    0x1a,		0x15,		21
    0x1b,		0x26,		38
    0x1c,		0x01,		1
    0x1d,		0x0C,		12
    0x1e,		0x00,		0
    0x1f,		0x00,		0
    0x20,		0x16,		22
    0x21,		0x0E,		14
    0x22,		0x06,		6
    0x23,		0x15,		21
    0x24,		0x00,		0
    0x25,		0x07,		7
    0x26,		0x01,		1
    0x27,		0x13,		19
    0x28,		0x00,		0
    0x2b,		0x00,		0
    0xfc,		0x00,		0
    0xfd,		0x00,		0
    0xfe,		0x00,		0
    0xff,		0x00,		0
    </registers>
    
    <frefa>
    100000000
    </frefa>
    
    <frefb>
    0
    </frefb>
    

  • Hi,

    I'm sorry for getting back to you so late. I went in the lab today and I realized I do not have an evaluation board to try the files you sent.

    However, I looked over them and I recommend the following things to debug the situation:

    - set the charge pump current to the max value, 3.2mA. Now it is set to 400uA.

    - read STATUS register 0x002 and look at the status bits starting with the ones that give you the state of the reference clock 6, 4 and 3:2.

    - you need the reference to be considered OK by the chip before the PLL can lock onto it.

    - then, if the reference is OK, the PLL should lock. 

    Petre