How to configure RTC supercapacitor charge current? And how long RTC can work without power with fully charged 0.07F capacitor?

Autonomous Machines Jetson & Embedded Systems Jetson Nano
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How to configure RTC supercapacitor charge current? And how long RTC can work without power with fully charged 0.07F capacitor?

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Please go through the below links

the PMIC datasheet for MAX77620 explains how to configure.

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Maybe this will help

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Here is a sample calculation:

t (s) = C * (Vmax – Vmin) / I

Vrtc safe voltage range: 3.3V to 1.65V, capacitor: 0.08F, Imax: 10uA,
So plugging in the values , t in seconds is

T = 0.08 * (3.3 – 1.65) / (10 * 10^-6) = 13200s

you can get online calculator also

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Thanks. That is, max77620 is installed on the sodimm module or is it integrated in tegra soc? I have a carrirer board circuit and there is no documentation for the module. Is there documentation for the module? And please tell me. In which device tree file is the configuration of the current and voltage of the battery charging stored?

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Thank you. It will come in handy.

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PMIC is in the CVM module. Not in the base board.

https://developer.nvidia.com/embedded/dlc/jetson-nano-product-design-guide

tegra210-porg-pmic-p3448-0000-a00.dts

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Thank you, bbasu. I checked. In the device tree, a charging voltage of 3 volts is set. But in fact, the supercap only charges up to 2.5 volts. Charged for more than a day. I will do the kernel assembly again. But this is strange. I use sources from R32.2.1