OP-1 Field USB charging on/off

Hi folks,
I connected op1f to ipad via usb-c to send midi out of ipad app to op1f. I didn’t want to drain ipad battery so I toggled the charging off on op1f (shift+com and press orange encoder so the lighting indicator has blue/grey background). Anyway the op1f is still being charged - I checked the battery status and also the led next to power switch is orange.
Am I doing anything wrong? Is this known behaviour/limitation?
Many thanks!

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…the same behavior happens while connecting to mac

Hey man! I am having same issue. When plugging my OP-1F into a usb c hub hooked up to my iPad and tx-6 I am getting some crazy feedback. I could eliminate it by unplugging the field, but turning off the charging in the shft+com menu did not work. Figure anything else out?

unfortunately not :frowning:
turn off charging works great on TX-6, OP-1F issue persists :frowning:

It’s insane that this hasn’t been addressed yet. I like others can’t turn charge off on my field so any midi fun I want to do with norns sounds like absolute trash

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That’s TE for you.

Hi guys,
my op1f has the same problem.

For your information I try to contact TE support and they sent me this:

“hi Massimo,

thank you for sending this!

we have forwarded this information internally, hopefully the development team will resolve this in a near future firmware update!

is this causing any other issues with your units performance?

don’t hesitate to contact us if you have any further questions! meanwhile, have a nice day.

teenage engineering support”

I hope they fix this problem in the next firmware update.



Same here still, op1f with fw 1.5.0, the power draw is the same after graying the background of the lightning symbol from red in COM settings, the only change is the mA Input limit shown in the Battery section in settings below the Charge percentage, which drops from 500/1000/1200 based on plugged source to 10 mA (when unplugged shows 100). Same for op1og fw 2.4.6.


I got recently a feedback from TE on the charging, reported above saying: “regarding battery charging, this function is mainly intended for usb ground loop isolation.”
Did not ask them (yet) if there was more that could be done with current hardware. Would be great though, to save the battery cycles.

Thank you !! It could make sense. However I still do not justify it as I would love to have working the way I expect :slight_smile:
Anyway, thanks for sharing your findings here :pray:

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I’ve sent this to TE:
I understand that the motivation on that field was to limit the humming noise, which seems to work, but to give the OP1F’s battery longer life is there anything more that could be done with it’s hardware, like controlling the current charging limit or ideally total battery bypass? It seems the device does limit the charge current to 100mA in the first couple seconds, then raises the charging current based on some negotiation with the charger. Could this be somehow controlled?

The response from TE support was:
“there is currently no way to control the charging, which is handled automatically.”