PGA900: I2C initialization write order difference between datasheet and PGA900EVM+USB2ANY

Toshihiro Watanabe

Part Number: PGA900
Other Parts Discussed in Thread: USB2ANY,

Hello,

I2C procedure is written in 7.3.16.2 of the datasheet but PGA900EVM+USB2ANY communication doesn't follow this procedure.

May this procedure difference be any issue on I2C communication? Why MICRO_INTERFACE_CONTROL write twice?

The attached is captured log by logic analyzer. Please refer it.

PGA900EVM_USB2ANY_communication.xlsx

We are facing I2C communication issue and investigating the root cause why we can't communicate with PGA900.

Best regards,

Toshihiro Watanbae

over 7 years ago

0 Scott Cummins over 7 years ago

TI__Mastermind 31655 points

Hi Watanabe-san,

Is this being tested with the EVM? Can you please post a picture of the EVM with the current jumper settings being used? Is there any problem using any of the other digital interfaces to communicate with the PGA900?

Regards,

0 Toshihiro Watanabe over 7 years ago in reply to Scott Cummins

TI__Genius 10235 points

Hello Scott-san,

We only use I2C. This test is done by PGA900EVM and USB2ANY. The picture of EVM will be posted later.

Best regards,

Toshihiro Watanabe

0 Toshihiro Watanabe over 7 years ago in reply to Toshihiro Watanabe

TI__Genius 10235 points

Hello Scott-san,

The picture of PGA900EVM attached.

Best regards,

Toshihiro Watanabe

0 Scott Cummins over 7 years ago in reply to Toshihiro Watanabe

TI__Mastermind 31655 points

Hi Watanabe-san

J9, J10, J4, and J15 should all be open if using voltage mode. These could potentially have an effect on the communication with the device.

Can you please test the other communication interfaces as well? SPI and OWI. For OWI you will need to close J12 and open J13.

Regards,

0 Toshihiro Watanabe over 7 years ago in reply to Scott Cummins

TI__Genius 10235 points

Hello Scott-san,

PGA900EVM works I2C. So we are asking why I2C initialization procedure is different from the datasheet and write twice.

Can you answer my question?

Best regards,

Toshihiro Watanabe

0 Toshihiro Watanabe over 7 years ago in reply to Toshihiro Watanabe

TI__Genius 10235 points

I mean PGA900EVM works but our prototype doesn’t work I2C.
Best regards,
Toshihiro Watanabe

0 Toshihiro Watanabe over 7 years ago in reply to Toshihiro Watanabe

TI__Genius 10235 points

Hello Scott-san,

I was misunderstanding. I2C didn’t work but become worked if I2C pull-up voltage changes from 5V to 3V.

Is there any issue if I2C pull-up resister set 5V?

Best regards,

Toshihiro Watanabe

0 Toshihiro Watanabe over 7 years ago in reply to Toshihiro Watanabe

TI__Genius 10235 points

Hello Scott-san,
I believe Pullup voltage of I2C =5V is an issue because absolute max exceeds. Is this over voltage possibility to make communication error?
Best regards,
Toshihiro Watanabe

0 Toshihiro Watanabe over 7 years ago in reply to Toshihiro Watanabe

TI__Genius 10235 points

Hello Scott-san,
It seems I2C pull-up voltage =5V is an issue for communication. It is resolved if the pull-up voltage sets properly.
Thank you for your support.
Best regards,
Toshihiro Watanabe

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PGA900: I2C initialization write order difference between datasheet and PGA900EVM+USB2ANY