@PJ_Glasso @reivilo
Hi
Please check this schematic:
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where you been sharkface? i missed you!
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Hi folks,
Was this ever resolved? Iām getting a similar issue with a 1.54 inch 3 colour displayā¦
(Also canāt attach a photo 
) Happy to share a photo if allowed to.
pictures are allowed once you level up some by reading more posts and hearting posts you like
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the guy above had two boardsā¦ the one that worked better seems to have a row of units, capacitors or resistorsā¦ i am wondering if it is an adjustable contrast?
its a shame when the unit is smaller than the controller
Hi, I tried to access the PDF, but only get:
This XML file does not appear to have any style information associated with it. The document tree is shown below.
AccessDenied
Access Denied
5PPZTERFD7H16QH3
0ifZip5uaTq5UN3DYIyrA7FJ20cIWS6YWXK3fIKbptyzrFnCfFHsINY7+r9kVNzesyv8Yn9612E=
Would you PLEASE be so kind and send a new valid link to the PDF?
thanks in advance and best regards, Jesse
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same issue as others, I cannot access this PDF - can you post an accessible one?
I just recieved this driver board from Digikey and am seeing that the battery charging doesnāt seem to be working. I have a XIAO S3 attached via the headers and the battery attached using the PH2 connector on the driver board and while it can all get power from the battery, it wonāt charge it when I connect USB to the XIAO. Am I missing something? I figured that charging via the XIAOās USB port would be the way to do it since theres no documentation to state otherwise other than the bullet point in the marketing materials stating that the charging ICs are on the board to simplify integration.
Can anyone help out here? Should I wire up a dumb usb-c plug to the VDD/GND pins on the driver board and use that? Seems like it might cause some issues since theyāre shared between the xiao and the board (and frankly, Iām not knowledgeable enough to properly make sense of the charging/bat portion of the schematic on the wiki.
I would post a new thread, but Iām unable to yet since my account is new.
@Charles_Waite XIAO S3 USB does not charge LiPo battery. Driver board likely needs its own USB input. Charging IC probably not connected to XIAO VBUS. Battery powers system but charger never enabled. Check board for separate 5V or USB-C input. XIAO pins alone usually donāt carry USB power. Do not inject USB directly into VDD pins. That risks back-powering and damaging the board. Use official power path shown in schematic. Send board link for exact confirmation.
check and make sure you got less than 3.7 v at the battery pads or it will assume it is charged and not send power
@loveforcircuits Thanks for the reply. Here is the board Iām talking about: ePaper Driver Board for Seeed Studio XIAO . It has charging logic and VBUS evidently is passed between XIAO and the board. Its quite literally designed for a XIAO to slot in on top and power the system and supposedly charge the battery. There are no other discrete power inputs on the board though all the XIAO pins are broken out right next to the headers which is very helpful and could allow you to wire up 5v to the VBUS pins.
That all beign said, I did some more testing and realized that it actually IS charging my battery. since it was at 3.94v it was basically trickle charging it. I measured voltage rise across the BAT+/- with it off then on to be only .02v so I didnāt notice it on my DMM previously. I left it overnight with the battery connected to the Driver boardās PH2 connector and the Xiao plugged into USB and connected to the board headers and battery voltage rose to 4.12v. So it IS charging, just very slowly.
@cgwaltney Yea it seems the charging logic is very conservative, which is totally fine for my use case, I just needed to to actually charge without having to add any seemingly redundant lipo charging hardware. The issue lay between the keyboard and chair, though I wish Seeed had some better documentation around the charging implementation, as its really not made clear at all. Maybe they can add that to their docs. Its compounded by the XIAO not showing the correct charging LED patterns (which makes sense as it doesnāt know its charging a battery) and the display driver board has no status indicators on it at all.
Either way, problem solved. Thanks for the diagnostic tips.
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I wish we had an intelligent charging module with IIC
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@Charles_Waite That makes sense now. Board is charging through XIAO VBUS passthrough.
Your earlier measurements caught near-float charging behavior. At 3.94V, charger current was probably already reduced. Small LiPo chargers taper current approaching full voltage. 0.02V rise is believable over short measurements. 4.12V overnight confirms charger functionality definitely works. Likely charge current intentionally limited for thermal safety. No need wiring external USB into VBUS pins. Your setup appears functioning as designed now.
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Yea I was expecting a much higher charging voltage, but this sort of slow charging is perfectly fine for my use case. Given the power handling ICs are directly below the XIAO on this board, Iām perfectly happy to trade charging speed for thermal stability in this sort of application, so Its all good. I just should have paid more attention to the DMM when I was taking my initial measurements! Derp.
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