OPA172: Increase in phase noise in ovenized oscillator

Part Number: OPA172
Other Parts Discussed in Thread: OPA171

Tool/software:

Hello,

 

So, the problem we're having is that we are seeing an increase in phase noise in our ovenized oscillator running at close to 100 Celsius. Because of that we're trying to see what would cause this problem.

Could you please check to see if there is any recall/known issues/PCN for the following product:

  1. OPA318AIDCK
  2. OPA172IDCKT
  3. SN74LVC1G00DCKR
  4. SN74LVC1G00DCKT
  5. LM4041CEM3-ADJ/NOPB
  6. LM4041CEM3X-ADJ/NOPB
  7. TPL0102-100QPWREP
  8. REF4132B25DBVRQ1
  9. TS12A12511DCNR
  10. LM4041CIM3-ADJ/NOPB

 

Thank you,

Nhan Tran

  • Hi Nhan, 

    For OPA172, this is recent PCN on the packaging changes. 

    https://mm.digikey.com/Volume0/opasdata/d220001/medias/docus/5858/PCN_20240203000.0.pdf

    I do not see any recent changes regarding the noise specification. Last noise specification change via PCN is back in 2014. 

    we are seeing an increase in phase noise in our ovenized oscillator running at close to 100 Celsius.

    Have you compared the OPA172's supply voltage rails in voltage ripple at approx. 100C? I do not have your schematic, so I am unable to say what may be the root causes. It could be also noise from reference voltage, oven's GND or measurement techniques etc.. Do you use differential probe to measure the change at the output of OPA171. 

    If you are able to send me the schematic, I can take a look. 

    Best,

    Raymond