ADC3221: Clock Cycles at Read Operation

Shinichi Inoue

Guru 19941 points

Part Number: ADC3221

Dear Specialists,

My customer is confirming ADC3221EVM and has a question.

I would be grateful if you could advise.

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We're confirming ADC3221EVM

The register value of ADC3221EVM was read using ADC3000_GUI.

At that time, when I checked the clock (SCLK) during read operation with the USB output signal, it was only 23 clocks, not 24 clocks in the data sheet described.

23 clocks are no problem, or 23 clocks are spec?
(There are 24 clocks during register write operation)

Could you please see attached the waveform.

ADC3221 register writing and reading waveform .pptx

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I appreciate your great help in advance.

Best regards,

Shinichi

over 2 years ago

+1 Chase W over 2 years ago

TI__Mastermind 19415 points

Hi Shinichi,

I've just confirmed on our EVM that there are 23 clocks for reading registers and 24 clocks for the register writes. This matches the behavior indicated on your uploaded powerpoint. Please see below images as well. Triggered on falling edge of SEN.

Read (23 clocks):

Write (24 clocks):

Regards

0 Shinichi Inoue over 2 years ago

Guru 19941 points

Hi Chase,

Thank you for your reply.

I understand your EVM is the same result.

I'll share your comment with the customer.

If the customer has an additional question, I consult you again.

I appreciate your great help and cooperation.

Best regards,

Shinichi

0 Shinichi Inoue over 2 years ago

Guru 19941 points

Hi Chase,

The customer has an additional question.

Could you please advise.

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I understand your EVM is the same behavior.

Is it a typo that the datasheet says 24-bit when reading resisters?

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I appreciate your great help and cooperation.

Best regards,

Shinichi

0 Chase W over 2 years ago in reply to Shinichi Inoue

TI__Mastermind 19415 points

Hi Shinichi,

I am checking with the team on this and will get back to you. Kindly await our response.

Thanks

0 Chase W over 2 years ago in reply to Chase W

TI__Mastermind 19415 points

Hi Shinichi,

The response from our design team indicates that the operation should be 24-bits. I will be checking this in our lab again soon. I will update you then.

Thanks

+1 Chase W over 2 years ago in reply to Chase W

TI__Mastermind 19415 points

Shinichi,

The read operation should be 24 bits. The issue is with the GUI itself in that it is only reading back 7 data bits. This should not affect ADC operation since the register writes to the ADC is correctly formatted. This only means that the data read back from registers on the low level tab will not be correct.

Thanks

0 Shinichi Inoue over 2 years ago

Guru 19941 points

Hi Chase,

Thank you for your reply.

I understand GUI has a issue.

I'll share this information with the customer.

I appreciate your great help and cooperation.

Best regards,

Shinichi

0 Shinichi Inoue over 2 years ago

Guru 19941 points

Hi Chase,

I shared your comment with the customer.

They'd like to improve the GUI, could you please share with your team.

If you have a plan, could you please inform.

The comment is listed below.

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We understand that there is a problem on the GUI side and there is no problem on the ADC side.

However, in that case, I think it would be better for TI to fix the GUI.(an image of fixing software)

In order to evaluate all the functions of ADC3221, it would be better to have a GUI that works properly.

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I appreciate your great help and cooperation.

Best regards,

Shinichi

0 Chase W over 2 years ago in reply to Shinichi Inoue

TI__Mastermind 19415 points

Hi Shinichi,

I will relay this feedback to our team.

Regards

0 Shinichi Inoue over 2 years ago

Guru 19941 points

Hi Chase,

Do you have any update?

I appreciate your great help and cooperation.

Best regards,

Shinichi

0 Chase W over 2 years ago in reply to Shinichi Inoue

TI__Mastermind 19415 points

Hello Shinichi,

I have not received a response from the design team. However, I imagine that there will not be an update for this GUI. I am now closing this thread, if your customer has any additional questions regarding the ADC3221EVM, please post via a new thread and we will be happy to assist.

Regards

Data converters

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ADC3221: Clock Cycles at Read Operation