# 12V DC killed LimeSDR-USB
**URL:** https://discourse.myriadrf.org/t/12v-dc-killed-limesdr-usb/7736
**Category:** General Discussion
**Created:** [18 October 2022 23:19 UTC](https://discourse.myriadrf.org/t/12v-dc-killed-limesdr-usb/7736 "2022-10-18T23:19:49Z")
**Posts on this page:** 5
**Page:** 1
### Author:  [@jtang](https://discourse.myriadrf.org/u/jtang)
#### Post date: [18 October 2022 23:19 UTC](https://discourse.myriadrf.org/t/12v-dc-killed-limesdr-usb/7736/1 "2022-10-18T23:19:49Z")
I’m curious if anyone else has encountered this? According to the documentation and schematics, the LimeSDR-USB should accept a 6-12V DC barrel plug (center-positive). However, when I plugged in a 12V DC adapter to my board, it immediately died and will no longer power up, either from DC or USB. No LEDs, no USB enumeration (dmesg / lsusb). It’s dead.
Are there known issues and/or fragile components that could help me narrow down the culprit?
Appreciated, thanks.
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### Author:  [@andrewback](https://discourse.myriadrf.org/u/andrewback)
#### Post date: [21 October 2022 18:38 UTC](https://discourse.myriadrf.org/t/12v-dc-killed-limesdr-usb/7736/2 "2022-10-21T18:38:36Z")
Tagging @zack.
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### Author:  [@jtang](https://discourse.myriadrf.org/u/jtang)
#### Post date: [23 October 2022 23:50 UTC](https://discourse.myriadrf.org/t/12v-dc-killed-limesdr-usb/7736/3 "2022-10-23T23:50:58Z")
Update: After reading a similar thread at: [I killed my LimeSDR... maybe - #2 by OrsonMaxwell](https://discourse.myriadrf.org/t/i-killed-my-limesdr-maybe/6101/2)
I supplied VCC\_INT with 4.8V directly on J21 and the board powered up and enumerated successfully.
I suspect this may be the same dead FPF3042 issue that user was experiencing. I’ll attempt the same removal of FPF3042 from the board and jump R167 to see if that resolves it.
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### Author:  [@jtang](https://discourse.myriadrf.org/u/jtang)
#### Post date: [24 October 2022 16:44 UTC](https://discourse.myriadrf.org/t/12v-dc-killed-limesdr-usb/7736/4 "2022-10-24T16:44:35Z")
Update: Removing the FPF3042 (IC25) and jumping R167 successfully allows the device to operate on USB power again. I’ve got a few new FPF3042’s on order - but at this point, given that fine pitch rework isn’t exactly my speciality, I might just consider it “fixed” rather than fixing it until it isn’t.
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### Author:  [@OrsonMaxwell](https://discourse.myriadrf.org/u/OrsonMaxwell)
#### Post date: [15 March 2023 09:06 UTC](https://discourse.myriadrf.org/t/12v-dc-killed-limesdr-usb/7736/5 "2023-03-15T09:06:17Z")
I didn’t bother resoldering the tiny bga chip - I’m not skilled enough, so I thought I’d do more harm than good. Glad my thread could help.