This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

TPS65988: SPI flash firmware update over I2C with Titan Ridge

Part Number: TPS65988

Hello,

Is the SPI flash firmware update over I2C feature usable when a Titan Ridge (TR) is on the SPI bus?

Also is it possible to do a first time programming of the flash memory using this feature or is this strictly for updates?

Thanks,

Chris

  • Hi ,

    1. we usually use different I2C port to do the flash firmware update and connect to Titan Ridge, why do you want to use one I2C port for those two function ?

    2. it is ok to do the first time programming.

    Best Regards,

    Kevin

    If this answers your question, Please click "This resolved my issue" button.

  • Hi Kevin,

    After some testing I figured out how to accomplish what I wanted to do.

    My worry about having the Titan Ridge in system is not around the I2C port but the SPI port that has the shared memory. The SPI device is servicing two masters (Titan Ridge and TPS65988) and I was unsure if there would be random signal crashing when using the reprogramming feature.

    To avoid this I use a 4CC command to put the Titan Ridge into reset while flashing the memory. Is it recommended that I have the TR in reset or is reprogramming possible with it in an active state?

    Thanks,

    Chris

    PS: I followed the required layout of having the TR on the TPS65988 I2C port 2 and I'm using the reprogramming feature on TPS65988 I2C port 1.

  • Hi Chris,

    it is ok to put the TR into reset while flashing the memory.

    Best Regards,

    Kevin

  • Thanks for the confirmation Kevin, one last question.

    In the TPS65988 datasheet, section 6.15 there are specs for using I2C at 1.8V which is not compatible with the Input High spec at 3.3V. To use the I2C at 1.8V can I simply swap the pull-up voltage rail from 3.3v to 1.8v or must the I2C lines be configured to operate at 1.8v?

    Thanks

  • Hi,

    I will check and reply to you soon.

    Kevin

  • Hi Christopher Cobbs,

    you can swap the pull-up voltage rail from 3.3V to 1.8V, the I2C input thresholds are set by LDO_1V8 by default. but if you use the LDO voltage on the TPS65988 as the pull up voltage, i suggest using LDO_3V3, it has higher output capability。

    Best Regards,

    Kevin

    If this answers your question, Please click "This resolved my issue" button.