Hi community,
Our customer have a question about i.MX7 SABRE board.
Please see the following image, it shows the connection of PMIC_ON_REQ signal.
PMIC_ON_REQ is push-pull output from Table 8 in IMX7DSHDG Rev.0, and RESET_B of reset IC is open-drain from TPS3808 datasheet.
If i.MX7 output PMIC_ON_REQ as High and reset IC output output RESET_B as low at the same time, we think output collision will be occurred and short will be also occurred as the red route on the following image.
So pull-down resistor should be added between PMCI_ON_REQ and RESET_B (at the black square).
Is our understanding correct?
Or the SABRE shematic is no problem with some reason?
Best Regards,
Satoshi Shimoda
Solved! Go to Solution.
Yes, you are right. R307 should be either not populated or be at least some 1 to 10 kOhm resistor to prevent extra current drain when the external watchdog Reset signal goes Low.
Have a great day,
Artur
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Yes, you are right. R307 should be either not populated or be at least some 1 to 10 kOhm resistor to prevent extra current drain when the external watchdog Reset signal goes Low.
Have a great day,
Artur
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Note: If this post answers your question, please click the Correct Answer button. Thank you!
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Hi Artur,
OK, we understood.
And please tell this problem to your SABRE development team to fix this problem on next revision.
Best Regards,
Satoshi Shimoda