TPS65987D: Use TPS65987 without external flash, initialize via I2C

Tony DiMichele

Part Number: TPS65987D

Pretty much a repeat of the thread here: https://e2e.ti.com/support/interface-group/interface/f/interface-forum/982027/tps65987d-use-tps65987-without-external-flash-initialize-via-i2c

Just need a way to dump the register settings binary file into the device at startup. I do not have an external flash, we were under the assumption that VBUS2 would be acting as a 5V source at startup with MISO = 0 and ADCIN1 = 0.15 but this appears to be incorrect. Is there a strapping solution to enable this behavior, or do I need to program the device with the register settings at startup? If so, any chance I can have access to the app note referenced in the ti support thread I linked above? I plan on using a Spartan 7 I2C bus to dump the static configuration into the device, and storing the data as a ROM directly in the Spartan. A strapping solution would be great though!

Thanks,

Tony DiMichele

over 2 years ago

0 Tony DiMichele over 2 years ago

Prodigy 20 points

Looking at the C Hex dump it looks like the the transactions are 0xADDR, 0x00 (start), 0xNo._of_bytes, 0xLSB, 0xLSB+1, ..., 0xMSB, 0x0F (stop)

If I just store this raw hex output in a ROM in my fpga, can I just dump it in at startup without any issues? Do I need to send the entire register's contents in one I2C transaction or can I apply a stop signal after I send each individual byte?

0 Aya Khedr over 2 years ago in reply to Tony DiMichele

TI__Mastermind 30902 points

Hi Tony,

Thank you for reaching out!

This is the document mentioned in the previous thread: https://www.ti.com/lit/an/slvae21a/slvae21a.pdf?ts=1686768548305&ref_url=https%253A%252F%252Fwww.ti.com%252Fproduct%252FTPS65987D

You can refer to Table 2 on page 11 for the ADCIN1 DIV values and their corresponding configurations.

I will look more into this and get back to you with a detailed response by Friday. In the meantime, feel free to look into the document and let me know if you have additional questions.

Best Regards,

Aya

0 Tony DiMichele over 2 years ago in reply to Aya Khedr

Prodigy 20 points

Any update?

0 Aya Khedr over 2 years ago in reply to Tony DiMichele

TI__Mastermind 30902 points

Hi Tony,

Thank you for your patience.

I am asking internally and will get back to you by EOB today.

Best Regards,

Aya

0 Aya Khedr over 2 years ago in reply to Aya Khedr

TI__Mastermind 30902 points

Hi Tony,

For boot strapping solutions, you can reference the datasheet here:

Tony DiMichele said:
If I just store this raw hex output in a ROM in my fpga, can I just dump it in at startup without any issues? Do I need to send the entire register's contents in one I2C transaction or can I apply a stop signal after I send each individual byte?

I need to verify with our firmware expert about this to be sure but I would recommend reading section 8.3.12.1 - 8.3.12.4 about I2C interfaces and the read register protocol.

Best Regards,

Aya

0 Ghouse Mohiuddin23 over 2 years ago in reply to Aya Khedr

TI__Expert 8290 points

You cannot write to all the registers overs I2C some configuration registers are readonly and they have to loaded as a patch load process.

0 Tony DiMichele over 2 years ago in reply to Ghouse Mohiuddin23

Prodigy 20 points

What do you mean by a patch load process?

0 Aya Khedr over 2 years ago in reply to Tony DiMichele

TI__Mastermind 30902 points

Hi Tony,

Thank you for your patience.

Patch load process is the patch bundle process flow outlined in the document provided in a previous response.

Best Regards,

Aya

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TPS65987D: Use TPS65987 without external flash, initialize via I2C