Fanstel USB840 Set Vdd from 1.8 to 3.3

RE: Fanstel USB840 Set Vdd from 1.8 to 3.3

ketiljo — Wed, 09 Feb 2022 13:23:25 GMT

According to the schematic, https://www.fanstel.com/s/USB840F-V6.pdf, the VDD pin is accessible at JS1. Connect this to an external 3 V supply and you should be able to set the regulator to 3.3 V with your programmer. Do not connect USB at the same time!

RE: Fanstel USB840 Set Vdd from 1.8 to 3.3

Prathik — Wed, 09 Feb 2022 13:06:35 GMT

Thank you for your response Ketiljo. I use Fanstel Dongle BT840. Is it possible to do it for this device.

I use JLink EDU programmer.

RE: Fanstel USB840 Set Vdd from 1.8 to 3.3

ketiljo — Tue, 08 Feb 2022 13:47:22 GMT

You probably have a programmer/debugger that can't handle 1.8V? Connect 3.0 V to VDD temporarily so that you can set this register,