Documentation for pyboard v1.1?

[gs2974]

Hi, I am trying to make a custom board based off of the pyboard v1.1, but have not been able to find a schematic anywhere. I have found documentation for previous pyboard versions, but would prefer to base my custom board off the newer version. Specifically, there is a component labelled ALW-551-R5 near pin X5 that I have been unable to identify.

If you can provide a schematic and/or information on this component, it would be greatly appreciated.

[chrismas9]

http://micropython.org/resources/PYBv11-schematics.pdf

[gs2974]

Thank you for sharing this document.

Comparing the pyboard v1.1 to the documentation, I am a little confused. When you download the document, you can see the part numbers of the components in the schematic by clicking on them, but they do not always match. Specifically, U2 (MCP1703 voltage regulator) and U4 (DNF MIC2005A-1YM5 current limiting power switch) came up as 3 and 5 pin chips respectively, of which there are none on my pyboard v1.1 (there is a 3 pin chip, but I believe this is Q1, the MOSFET). There is an 8 pin chip by X5 on the right (check this picture: http://micropython.org/resources/pybv11-pinout.jpg) that is, as far as I can tell, undocumented in the pdf schematic for pyboard v1.1. Would someone happen to know what this 8 pin chip is and why I can't find U2 and U4 on the pyboard v1.1? Is it possible that this 8 pin chip is a combination of U2 and U4?

I will also note that I have compared to the pyboard v1.0b, where U2 is instead an MCP1802 with 5 pins, and there is one 5 pin chip on this board (check out the image at: http://docs.micropython.org/en/latest/p ... ckref.html), but I am unsure whether this is U2 or U4.

[pythoncoder]

The DNF (do not fit) chip pads are on the underside. As for the 8 pin chip why not use traditional reverse engineering techniques? Examine it with a strong lens to see if there are any visible markings. Failing that, use a meter on a low ohms range to check its connections to see if it is, in fact, the voltage regulator.

I assume you have actually got a Pyboard? Commissioning a variant without a reference board for comparison will add needless difficulty.

[chrismas9]

U2 is the 8 pin chip you refer to. It is an MCP1703 in DFN8 package with thermal pad (pin 9 on the schematic). When you click on U2 in Acrobat Reader it shows the correct manufacturer and Digikey part numbers for the DFN8 package. See screen shot attached.