http://imgur.com/a/xY4rZ
Its capacitor c106, thanks
- mahjongg
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Re: Does anyone know the value of this capacitor?
full schematics of the PI3B have not been released, and C106 doesn't appear in the reduced schematics, so nobody can help you.
I looked in the schematic of the PI2 B but C106 also does not exist in a PI2B.
I guess C106 has something to do with USB current limitation and might not be critical, I would simply try if a 100nF cap works.
I looked in the schematic of the PI2 B but C106 also does not exist in a PI2B.
I guess C106 has something to do with USB current limitation and might not be critical, I would simply try if a 100nF cap works.
Re: Does anyone know the value of this capacitor?
The component numbering seems to be retained with newer Pi versions.
Previously, mahjongg has confirmed C106 as 220nF on a B+. I'd be confident that is still the case on a Pi3. It's likely the exact value won't matter anyway if it's a decoupling capacitor, and may even work without it.
Edit: it def is there on a Pi2, to the left of D3 on the PCB around the USB current limit circuitry.
Previously, mahjongg has confirmed C106 as 220nF on a B+. I'd be confident that is still the case on a Pi3. It's likely the exact value won't matter anyway if it's a decoupling capacitor, and may even work without it.
Edit: it def is there on a Pi2, to the left of D3 on the PCB around the USB current limit circuitry.
- mahjongg
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Re: Does anyone know the value of this capacitor?
ah yes indeed, I looked in the schematic of the PI1 revision 2.1, and obviously it doesn't have the USB current limiter.
But yes I have previously found C106 to be 220nF, indeed in the current monitor.
I agree that the RPF does not seem to renumber previously used components in new schematics.
But yes I have previously found C106 to be 220nF, indeed in the current monitor.
I agree that the RPF does not seem to renumber previously used components in new schematics.
Re: Does anyone know the value of this capacitor?
Awesome, thanks. So, to be clear, the pi can work without it?
Re: Does anyone know the value of this capacitor?
Well in this case it seems to be part of an RC time constant / delay, not decoupling - see Burngate's diagram in the link I gave.
It's there so that the current limiting switch can be turned on quickly via the diode, but turned off with a delay while discharging through the resistor. Why that behaviour is needed eludes me right now!
It's there so that the current limiting switch can be turned on quickly via the diode, but turned off with a delay while discharging through the resistor. Why that behaviour is needed eludes me right now!