Identifying a small part on a board | Betaflight | Page 1

late herald Jul 18, 2025, 10:08 AM

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Any idea on what this part could be, and what it could be doing for a substitute? The picture is from a healthy, brand new board, and this component is damaged on a board I'm trying to have repaired

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I think it reads "Z 3 11", but that doesn't turn up any useful results for me

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It might also be reading "2 3 11", but I'm not sure

old basin Jul 18, 2025, 10:23 AM

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late herald Any idea on what this part could be, and what it could be doing for a substitute...

what board is this?

late herald Jul 18, 2025, 10:39 AM

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old basin what board is this?

X12 ELRS Pro v1.1 AIO

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by happymodel

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https://www.happymodel.cn/index.php/2023/11/15/x12-elrs-pro-v1-1-5-in-1-aio-flight-controller-built-in-2-4g-elrs-v3-0-and-openvtx/

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This exact one

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I've looked around, I wasn't able to find any useful schematic or documentation regarding this board

late herald Jul 18, 2025, 12:51 PM

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I desoldered it on a sacrificial/already damaged board, it's only got two pads under it

old basin Jul 18, 2025, 2:19 PM

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looks to be between a GND and VCC plane, so maybe a diode or something similar

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that's one of the very few things that make sense in a place and package like this

dawn ice Jul 18, 2025, 4:06 PM

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With a diode you'd expect some kind of marking at the cathode. Could be the angle of the light on the pictures, but I don't see any polarity marking?

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Like that diode at the top left with 'E9' and clear cathode markings

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Not sure what it is though 🤷‍♂️

old basin Jul 18, 2025, 4:54 PM

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dawn ice With a diode you'd expect some kind of marking at the cathode. Could be the angl...

I thought it wasn't Z311 and those two lines could be the polarity markings

dawn ice Jul 18, 2025, 5:19 PM

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Aahh, makes sense, a diode with just "Z3" marking

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Could be perhaps a PDZ3.3B zener diode, 3.3V?

ebon sphinx Jul 18, 2025, 7:46 PM

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maybe it is this : https://www.nexperia.com/product/PESD5V0S1UL or similar

Nexperia

PESD5V0S1UL (Unidirectional ESD protection diode)

PESD5V0S1UL - Unidirectional ElectroStatic Discharge (ESD) protection diode in a SOD882 leadless ultra small Surface Mounted Device (SMD) plastic package designed to protect one signal line from the damage caused by ESD and other transients.

dawn ice Jul 18, 2025, 8:46 PM

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That diode has "G2" as marking code.. I can't find any other ESD diode with "Z3"

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BZX584B3V0 also has "Z3." but with a dot apparently according to the datasheet. But a 3.3 V device makes more sense probably I'd say

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If you can measure the exact dimensions, we could narrow it down according to the package.

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Some other manufacturer says their BZX584B5V6 zener has the "Z3" marker.... Sigh..

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Lots and lots of devices: https://www.alldatasheet.com/view_marking.jsp?Searchword=Z3

Z3 Marking, Z3 Datasheet

Marking: Z3. Part #: PDZ3.3B. Package: SOD-323. Datasheet: 143Kb/9P. Manufacturer: NXP Semiconductors. Description: Total power dissipation: max. 400 mW. 155 Results.

late herald Jul 18, 2025, 11:06 PM

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Yeah, I think "it's a diode" is currently the most promising theory

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I emailed the manufacturer so far though, and found a few posts on reddit confirming that they indeed respond to requests like those

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So hopefully that'll get me the exact part number

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Z3 is insanely ambiguous

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I also found it on another board where it seems to be in a black plastic package, and I think it's polarity lines and not 11

late herald Jul 19, 2025, 8:53 AM

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It's this
https://www.digikey.com/en/products/detail/nexperia-usa-inc/PTVS7V5Z1USKYL/6576001

DigiKey Electronics

PTVS7V5Z1USKYL | DigiKey Electronics

Order today, ships today. PTVS7V5Z1USKYL – 13.5V Clamp 17A Ipp Tvs Diode Surface Mount DSN1608-2 from Nexperia USA Inc.. Pricing and Availability on millions of electronic components from Digi-Key Electronics.

late herald Jul 19, 2025, 9:24 AM

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guys
it all makes sense now

#Identifying a small part on a board