[NMatringe]

Hello
The problem has come back in another form, the PMIC won’t startup once reset. This is linked to a glitch in the 5V input (how much current does this module draw ? I’m amazed)
After lots of browsing through TI forums we found that the PMIC is sensitive to brown-out and can lockup, exactly as we observed. The case is also mentioned in the OSD3358-SM-RED User’s Guide on page 43.

Apart from adding insanely huge amounts of capacitance on the 5V supply, is there anything that can be done without any redesign ?

Thanks

N. Matringe, Alciom

[NMatringe]

The 1.8 V is the first rail to power up (LDO1 output).

After investigations, the problem is related to the capacitors on the 5V input (generated by a DC/DC boost) and SYS_Vout. I put more capacitance on the 5V converter and less on SYS_Vout and now it works.
Strange it worked fine on the first batch, though…

Thanks
Nicolas

[Author]

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