For all who are waiting for results: i got the Huawei E3331 modem working right now. I am still at the internal 3.3V sensor port with the power source. So what did the hack? I ordered a new step-up regulator to power the device. the new one is called U3V12F5 and has a high power transistor on board. With this there is enough current to power high consumption usb stick without any problems. Measurements are about 12x6x3mm and with this it is possible to hide everything under the backcover including the Huawei modem. The Lenovo is powering up without any problems after this there is the usb modem found by windows and you can connect to the service provider without any problems. I made a test to surf around 10 minutes only with the modem activated and everything getting really smooth. So tomorrow there should be a new device arriving here. I will make some hardware tests and if all is good i will do another disassemble/teardown video from this.
Additionally I plan to make a video coverage of the Lenovo miix 2-8 with working modem too but this will take some days. stay tuned.
If there is someone out there who is interested in my miix maybe with the wires still connected to get usb devices working internal please feel free to contact me. For those who dont want wires I can dismantle everything too to bring it back to stock device.
this is awesome. can u pls make a diagram or tutorial which wires connect to which ports? much appreciate it. thank you very much n great job!
hi luke,
yes i will do a summary for the steps to get high power usb devices working inside the miix.
please give me some time fo this…
thx daniel
hello i have a question do you think this voltage regulator could work with the huawei e3331 (http://www.pololu.com/product/799)? since this is the only available voltage regulator available in my place. thanks in advance
hi luke,
looks great so far. give it a try. try to make measurements with the huawei e3331 connected if there is a voltage drop down. would be nice to get feedback if you are good with this dc-dc regulator. so maybe we can make a sheet with compatible rehulators in future.
Since I m no expert in this stuff I only can solder n hope it works. But if it succeeds I ll inform U abt it
hi i have question how u do u noe which step up voltage regulator will work? the last link i showed u the voltage regulator is too thick n wont fit under the tablet cover. i found out a new one out of ebay (http://www.ebay.com.my/itm/2pcs-DC-5V-1-5A-Volt-Voltage-Regulator-Convert-Step-up-USB-Power-Module-IN-1-5V-/271060629134?pt=LH_DefaultDomain_0&hash=item3f1c78f68e) but i m not sure it will work or not. can u give me advice on this? the voltage input output seems right but im not sure about the current issue. thank you
Hi Luke,
i checked the specs and this one should work so far. i will go only for the specs for choosing a special regulator. The pololu ones are really tiny and the specs satisfied my needs so far. the huawei e3331 needs peak currents higher than 600mA. so the regulator should provide marginal more current. so i make measures when connected mine to see if the voltage drops when the peaks reach the regulator. if the regulator can not handle the higher currents it should reset or the voltage will drop down. the conversion efficiency and the Quiescent Current is important to. the efficiency should be as high as possible. 100% efficiency is the best but not possible regarding physics.
the Quiescent Current is important not to drain battery much when in suspend mode.
hope that you get it managed so far. may i ask where you from?
Daniel
thanks for the info. i m planning to use my usb 4g broadband to work with my tablet, need it for my study. btw i m from malaysia.
i will be in malaysia in december but only for stopover to philippines…
feel free to contact me if you have questions. i can offer you a skype call if you have all the stuff there.
cya daniel