OpenIMU330BI - Decoupling Needed? Eval board doc...

Hi There,

Probably a non issue, but...

I'm about to turn a board that is based on the OpenIMU330BI, usually, I look at the eval board and mimic that, but the doc below lists the DMU380 as the eval, just like the OpenIMU300.

https://buildmedia.readthedocs.org/media/pdf/openimu/latest/openimu.pdf

I just got my OpenIMU380 eval board in, and indeed, it looks just like the OpenIMU300 board.

The OpenIMU330 is pin / form factor adapted to be in OpenIMU300 form factor. The OpenIMU330 appears to be purely passively pin adapted by a small PCB. I dont see any capacitors.

Main question(s):

Is it possible to get a copy of the OpenIMU330 to OpenIMU300 pin adapter PCB schematics?
Also, are any local decoupling capacitors needed, or are the OpenIMU330's decoupling needs fully accounted for under the lid?

@Adam-Jackson Hi Adam jackson,

  1. For the OpenIMU330BI BGA package unit, the recommendation peripheral sch interface:2019-11-12_08h58_34.jpg 2019-11-12_08h58_16.jpg

The voltage range of the unit VIN if from 2.95V to. 5.5V.

2.For the OpenIMU330BI EVB board, pin to pin with OpenIMU300ZI unit.
2019-11-12_08h50_12.jpg

Is there an internal pulldown on BOOT0, or should that be added on the board if not using that pin?

@Jack-Morrison Yes, there is 10K pulldown internal connected with boot0/PH3.

The drawing above shows the bottom view of the BGA package with A1 at lower right, which fits with the top view's dot on lower left. Can I suggest that the drawing at https://openimu.readthedocs.io/en/latest/330BI/mechanical.html also label the pin view as bottom view (so a mirror image of the PCB footprint)? More importantly, the pin view in the spreadsheet at https://openimu.readthedocs.io/en/latest/330BI/pinout.html is labeled "top view" when in fact it's the bottom view (rotated but not mirrored).

@Jack-Morrison Hi Jack, thanks for your advise, we will update the document shortly.

https://forum.aceinna.com/topic/118/openimu330bi-error-in-openimu330bi_pin_definition-xlsx

Now I've got to spin 5x boards!

Also be aware that the Mouser parts library made the same error, then fixed it (after I used it), while also updating their terms and conditions.

I'm hoping maybe someone at Aceinna might do the right thing and send me 5x new IMU330's 😉

alt.png

Could you also please show the axis orientation on the mechanical drawing?

@Jack-Morrison Hi Jack, please check the axis orientation 2020-04-13_13h47_49.jpg

Thank you. (Puzzling that the data interface selection would matter)

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