LimeSDR Mini Fails to Respond on USB - RMA Requested

I have a LimeSDR Mini V1.2 (purchased on 20 March 2019) that on initial arrival responded OK, and had its firmware/gateware upgraded to 6/1.29 (using LimeUtil on a Raspberry Pi) successfully.

On the next attempt at use, it failed to respond to USB. It is not listed in lsusb on a Raspberry Pi, and on Windows 10 it says “Device Descriptor Request Failed”. This is the same for USB2 or USB3 sockets on the PC, and the same computer responds properly to a working LimeSDR Mini.

Neither LimeUtil nor the LimeSDR_Mini EEPROM programmer can see the device (but they can both see a working LimeSDR Mini).

The on-board LED flashes red/green when it is plugged into a USB socket, the power supply rails seem normal and I cannot see any sign of mechanical damage. I can’t access the device serial number, but the sticker on the underside of the board is 3121476.

Do you have any other ideas, or is RMA the only option?


Dave, G8GKQ

@Zack, anything else to try?

Could you download FT60X configuration utility, run it on Win10 machine. Connect LimeSDR-Mini, push Read Configuration button at the right bottom edge of the window. Paste print screen here, please.

Thanks @Zack

Running the tool with the LimeSDR Mini connected to a USB2 port, I get:

No device is connected to the machine!
Please connect a device!

On a USB3 port I get:

I did run the tool before plugging in the Lime to USB3 and was surprised that there was no Windows “Device Descriptor Request Failed” message when I plugged the Lime in.

I note that the USB 3.0 Controller IC on the LimeSDR seems to run very hot - but I don’t know if this is normal, because I normally only run USB2).

Is it something that I can reprogram?



Hi @DaveG8GKQ,

It looks OK.
Do you see the board in Device manager?

Hi @Zack

I only see the Lime in Device Manager if I start the FT60X Chip Configuration Programmer, then plug the Lime into a USB 3 port. If I just plug the Lime in without the Programmer running, the PC does not see it. Neither does it see the Lime ever from USB 2 ports. Both ports work perfectly with a known good LimeSDR Mini.

If I just plug the Lime into USB 3, I get this response:

C:\Users\dave>LimeUtil --make
Make device
No available device!

But if I run the Programmer, query the Lime and then run make:

C:\Users\dave>LimeUtil --make
Make device
  Device name: LimeSDR-Mini
  Expansion name: UNSUPPORTED
  Firmware version: 6
  Hardware version: 2
  Protocol version: 1
  Gateware version: 1
  Gateware revision: 29
  Gateware target: LimeSDR-Mini
  Serial number: 0x1d42599db5f945
  Free connection... OK

So it seems that it comes back to it not responding to a device descriptor request without help from the FTDI Programmer.

And I just burnt my finger on the USB 3.0 Controller IC unplugging it… Note that I had never used the USB3 ports on this Win 10 machine until we started this troubleshooting (they are around the back, on the floor!).


Very strange, never saw behavior like this before. RMA, please. And sorry for inconvenience.

Thanks, Dave