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I'm designing the power circuit for the \$V_{BAT}\$ portion of an STM32 microcontroller, using a supercap to hold the charge when the main is off.

I was calculating which resistor I should charge the supercap through, but I stumbled on the specifications:

Supercap specifications

What is the meaning of the MAX current at 30 min. column ? It does not seem to be the absolute maximum rating.

The capacitor charging current will drop exponentially, but I don't know from these specifications if it can withstand 150mA for 10-20 seconds when charging the capacitor from 0V.

The capacitor case is can-like with a diameter of ~17mm, and the specs does not specify power ratings for the case.

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can withstand 150mA for 10-20 seconds when charging the capacitor from 0V

It cannot. Maximum voltage is 5,5 volts, and its ESR is 65 Ohms => max current is about 85 mA.

What is the meaning of the MAX current at 30 min. column ?

The datasheet has the answer: It is the residual current after 30 min. charging time (from completely discharged).

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