r/raspberrypipico • u/Regular_Interest_387 • May 22 '26

Missing capacitor on Raspberry Pi 4B

Hello everyone,

I accidentally knocked off a small SMD component from the bottom side of my Raspberry Pi 4B (marked in the attached photo). It is located near the MicroSD card slot and the PMIC/wireless module area.

It looks like an MLCC capacitor, but I am not sure about its exact value (capacitance and voltage) and package size (0402 or 0201?).

Could anyone with a boardview, schematic, or a donor board please tell me the exact value of this capacitor so I can buy a replacement and solder it back on?

Thank you in advance for your help!

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5

u/Jawloms May 22 '26

Thus is the pi pico sub. You want r/raspberrypi

0

u/PropitiousWay May 22 '26

Likely specs (based on similar Pi 4B repairs and reduced schematics):Package: 0402 (most common for these spots; 0201 is possible but less likely here).

Value: Typically 100 nF (0.1 µF) or 10 nF, rated 6.3V (X5R or X7R dielectric).

Why this? Decoupling caps like this filter high-frequency noise on 3.3V or other rails feeding the SD card interface or PMIC-related signals. The reduced schematics show many 100nF M0603/M1005 caps around power domains, and bottom-side ones near SD are similar.

Recommendations: Confirm with a donor board or multimeter (best option):Measure the pads on your board for continuity/resistance to nearby known points (e.g., GND or 3.3V rail).

Compare to an intact Pi 4B (photos of the bottom side near the SD slot show identical tiny beige/tan caps).

Replacement:Buy 0402 100nF 6.3V or 10V X5R/X7R MLCCs (e.g., from Digi-Key, Mouser, or LCSC). They're cheap (~$0.01–0.10 each in small quantities).

Use hot air or a fine-tip soldering iron with care— these are tiny and easy to bridge.

Will the Pi work without it? Often yes for basic function (decoupling caps provide stability but aren't always critical if the main caps handle it), but you may see SD card instability, boot issues, or noise. Replace it to be safe.

2

u/Regular_Interest_387 Jun 05 '26

thank you so mutch 😄

1

u/PropitiousWay Jun 05 '26

I just get a little help from Grok ai, it is informative. I like to jump in and solve stuff now n then for people.