32MHz & 32.768KHz Crystal Part Number

[Afzal]

Dear Team,

Please help us to confirm the part number of the 32MHz & 32.768KHz Crystal part Number-
1. As per the mentioned parameter of the 32MHz Cryatal in the BOM file of NRF52833 
-XTAL SMD 2016, 32MHz, Cl=8pF, Total Tol: ±40ppm Please confirm the Tolerance and ESR value as well.


2. As per the mentioned parameter of the 32.768KHz Cryatal in the BOM file of NRF52833 
  -XTAL SMD 3215, 32.768kHz, Cl=9pF, Total Tol: ±50ppm .

 -Please confirm if it is ok if we use XTAL-3215-32.768K-9pF-20ppm crystal it is in our Stock. Please confirm the tolerance will be ok for it.


Please let me know if there is any query.

ATLANTA SYS
Regards,
Syed Afzal
Hardware Design Engineer 
7503601370
  

[haakonsh]

Hey Syed,

I don't know what crystals you are referring to, can you share the manufacturer part numbers for the two crystals you want to use?

You can also double-check their specs with our crystal oscillator el-specs; 64 MHz crystal oscillator (HFXO), and Low frequency crystal oscillator (LFXO). 

BR,
Håkon Holdhus

[Afzal]

Hello Hakon,

Thanks for your reply.

Please clear up my query about the selection of both crystals (32MHz & 32.768KHz) for nRF52833.
1. As per the defined parameter of the 32MHz Crystal in the BOM file of nrf52833 is XTAL SMD 2016, 32MHz, Cl=8pF, Total Tol: ±40ppm. in this please clear the tolerance level which is better for the design. As per my knowledge if we select the low tolerance 10 to 30 ppm will be better please correct me if I am wrong.

2. As per the defined parameter of the 32.768KHz Crystal(which is used for the BLE) is XTAL SMD 3215, 32.768kHz, Cl=9pF, Total Tol: ±50ppm but I am having the same different in Tolerance i.e. +-20ppm. Please let me know if it will be ok if we use the 20ppm Tolerance.

Please feel free to contact me in case of any queries.

ATLANTA
Regards,
Syed Afzal
Hardware Design Engineer 
7503601370

[haakonsh]

1. If the total tolerance is lower, then yes, it is generally better. 
   
   
• Afzal said:

  Total Tol: ±50ppm but I am having the same different in Tolerance i.e. +-20ppm.

What do you mean by 'the same different tolerance? 

Either way, a lower total tolerance is generally better. 

If you have any particular crystals in mind, please share the part numbers so that we can share the same context.

[Afzal]

Hello Haakonsh,

I mean to say I am having the +-20ppm Tolerance.
1. Please confirm whether the other parameter(XTAL SMD 2016, 32MHz, Cl=8pF)is ok or not. 

2. Please confirm whether the XRCGB32M000F2P2CR0 32MHz part number will be ok or not.

[haakonsh]

XRCGB32M000F2P2CR0 will not be okay:

1. Max drive level is 3x above spec.
   
   
2. ESR of 70Ohm is likely out of spec, but unknown. Because Co is not specified the ESR of the given crystal should be considered as out of spec.
   
   
3. Max tolerance can get too high ( > 40ppm) under certain conditions. Max tolerances includes nominal + temperature shift/drift + aging. 

[Afzal]

Please help me to select the crystal part number.

Also please clear the required parameters of the 32MHz crystal.  

[haakonsh]

haakonsh said:

You can also double-check their specs with our crystal oscillator el-specs; 64 MHz crystal oscillator (HFXO), and Low frequency crystal oscillator (LFXO).