Quick-jack power issue

[lpcware]

Content originally posted in LPCWare by amrendra.kumar on Tue Nov 11 15:01:55 MST 2014
I have recently bought few NXP based Quick-Jack EVM.This EVM works fine with nexus phone when battery is there on it.

As soon as i remove the battery from the EVM it stops working. Do i need to do change any jumper settings to work only on jack power.

My assumption is that this EVM should work on power harvested through Audio jack.

Has anybody faced this issue before.

[lpcware]

Content originally posted in LPCWare by david.ryoo on Tue Dec 09 21:01:23 MST 2014
@LPCWARE Team,

The documents(AN11552_1_0.pdf) provided by NXP clearly mentioned the board can be worked only with smartphone power and that's why I bought the board. I have same issue with Amrendra, it doesn't work without battery power even if I just use board as it is.

Also AN11552_1_0.pdf mentioned plain 21kHz sine wave and 3.2V from smartphone power, but I couldn't get it in my measurement. when I go through the android Application source code, it's impossible to get 21kHz sine wave.How did you get it?

Regards,
David

[lpcware]

Content originally posted in LPCWare by amrendra.kumar on Thu Nov 13 08:55:06 MST 2014
I have tried with nexus 4 phone after removing U6, however it didn't work-out.

I need to check without battery since wanted to develop our own quick-jack which can work without battery.

Any other suggestion on working without battery.

Thanks
Amrendra

[lpcware]

Content originally posted in LPCWare by Magicoe.Niu on Thu Nov 13 02:08:38 MST 2014
Hi,

Pls removed the reset chip 'U6' and use iphone to test this function without battery. Some Android equip can not powered enough current, pls use iphone.

We strongly suggest customer use extenal battery, most of customer use it. External battery can make your system more reliable.

Thanks!

[lpcware]

Content originally posted in LPCWare by lpcxpresso-support on Wed Nov 12 00:49:42 MST 2014
To quote the FAQ available from: http://www.lpcware.com/content/project/smartphone-quick-jack-solution

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Quote:
Q. Why is there a CR1220 battery on the board?
A. The amount of power Quick-Jack can draw from the phone, mainly depends on the make/model of the phone. Some phones may not provide enough power (though this is ought to be rare), so in that case Quick-Jack can run off the battery. This increases the number of phones Quick-Jack is compatible with. It may also help in providing enough power e.g. during flashing of the LPC800’s firmware.

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Regards,
LPCXpresso Support