Does VIN charge the LiPo on Inkplate 13SPECTRA?

k_borek535 · September 23, 2026, 10:25am

Hi,

I’m integrating the Inkplate 13SPECTRA into a device and I’d like to confirm how the power path works.

I plan to power the board from an external regulated 5 V supply connected to the VIN and GND pads, while also keeping a 3.7 V LiPo battery connected to the battery connector.

Could someone confirm:

-Does 5 V applied to VIN also power the onboard LiPo charging circuit?
-Is VIN electrically connected to the same power path as USB-C VBUS?
-If 5 V on VIN disappears, will the board automatically continue running from the LiPo battery?
-Is there any risk of backfeeding or any special protection required when using VIN together with the LiPo?

I couldn’t find the complete 13SPECTRA schematic in the public hardware files yet. If the schematic is available somewhere, especially the power-management / battery-charging section, I’d be grateful for a link or PDF.

Thanks!

fran · September 23, 2026, 11:54am

Hi @k_borek535

It does
It is
It will
There isn’t any risk

Attached below is the schematic of the board

Soldered Inkplate 13 SPECTRA Schematic.pdf (1.4 MB)

k_borek535 · October 5, 2026, 6:23am

Thanks. One last thing so I can do this safely:

Could you please show me exactly which two pads on the Inkplate 13SPECTRA PCB should be shorted to bypass the ON/OFF switch?

Ideally, could you mark them on a photo of the board or send a close-up showing the exact location of the R14 / bypass pads?

I don’t want to bridge the wrong pads, because the silkscreen around that area is not clear enough for me to identify R14 with confidence.

If possible, please also confirm:

whether those pads should simply be shorted with solder,
whether a 0 Ω resistor is preferred,
and whether shorting them guarantees automatic power-on whenever VIN is present after a complete power loss / fully discharged LiPo.

The board will be sealed inside an enclosure, so manual access to the power button will not be possible.

Andrej · October 5, 2026, 6:53am

Hello @k_borek535

In the images below, I’ve marked resistor R14.

You can either bridge those two pads with solder or fit a 0 Ω resistor. Both give the same result: constant power regardless of the power switch position.