i.MX25 Vref current of ADC

[sugiyamatoshihi]

Hi,

When ADC of i.MX25 use external reference mode, it connect external voltage reference to REF pin. At that time, How much current sink into REF pin?  It meed max current data to design Vref generator.

There is no data on data sheet.

Best Regards,

Sugiyama

[gusarambula · Accepted solution]

Hello Toshihisa Sugiyama,

I was looking at the available documentation and indeed the Vref current is not characterized and there is no reference value for it.

An alternative here would be estimating the maximum Vref current which would be less than the current required by NVCC_ADC, which is given by the i.MX5 Datasheet. This is a very gross estimate, but it would ensure that the Vref keeps stable during the AD conversion.

My apologies for the inconvenience. I hope this helps!

Regards,

[sugiyamatoshihi]

Hi, gusarambula,

Thank you for answer.

I'd like to confirm.

Do you means current spec of i.MX25 NVCC_ADC include current when Vref is self reference mode?

Best Regards,

Sugiyama

[gusarambula]

Hello Toshihisa Sugiyama,,

Current specs of i.MX25 NVCC_ADC reflects the current consumption of the ADC module as a whole regardless of the mode. Vref current consumption is not characterized but it should lower than this number.

Mu apologies for the inconvenience caused by not having Vref characterized but I hope this helps.

Regards,

[sugiyamatoshihi]

Hi,

Does someone know ?

Best Regards,

Sugiyama