TeleDecoder

[chethankarandikar]

No description provided.

[chethankarandikar]

@EDED2314
added the link to the schematic

[EDED2314]

lgtm (thanks!)

[KacperParaniuk]

Symbol Conventions ✅

• There are some symbols in the general libs folder that should be put in their own symbol library but those are not used for this project thus we can fix it once we merge.

Footprint Conventions ✅

3D Models ✅

Schematic Style 🟨

• The radio chip symbol could be better. The power pins (5,12,13,15,25,28,22,27) could all be combined into one with the others set as invisible and also moved to the top of the symbol as this is power. and gnd can be put to the bottom if we want to keep following this convention.
• l noticed net labels were used rather than hierarchical labels. Is there a reason for this? Also if we want to be consistent with other designs we should replace these to be the hierarchical labels.
• Additionally, within the box the following convention is not followed: "The box title describes the general functionality while the subtitle describes the main component partnumber or other design defining information."

Routing 🟨
I looked at a bit of the routing because I was curious about it and how the RF matching stuff was done. And how we implemented it with relationship to the teledongle.

I noticed that it was different from what we have done and was wondering if potentially this could result in an issue in the black magic world of RF.

someone with more RF knowledge can answer.

[tjmcmanamen38]

I noticed that it was different from what we have done and was wondering if potentially this could result in an issue in the black magic world of RF.

someone with more RF knowledge can answer.

Yes agreed 100% on this, I didn't really look over this board much until it was already done and didn't catch this in time but this is definitely something to change for future revisions.

[tjmcmanamen38]

The Crystal_NDK.kicad_sym library is not unique enough to have its own library and should be removed and replaced with the generic Crystal_GND2 symbol. Though credit where credit is due - the naming is good!

[tjmcmanamen38]

The radio chip symbol could be better.

Reasoning for this is that it's a KiCad default library (which you would think these would follow the KLC...). Your discretion if you want to change it.

However I would caution against combining all of the power pins, at minimum DVDD and AVDD should be kept separate. And I'm not sure enough as to the differences between all of the individual pins to know if they should be kept distinct or not, would have to look more at the datasheet.

[tjmcmanamen38]

Additionally, within the box the following convention is not followed: "The box title describes the general functionality while the subtitle describes the main component partnumber or other design defining information."

Yes this would be a good thing to change, I'd also change the SMA Connector box to be called 'RF Front End' or 'RF Matching Network' or something of that sort.

And generally I have liked to standardize the text size for the major boxes (eg microcontroller, usb, rf, radio, regulator) to 2mm rather than 1.27mm in addition to adding the main part number.

[tjmcmanamen38]

net labels were used rather than hierarchical labels

Yeah biggest thing here I think is just to make sure we're being consistent - USB data lines use hierarchical while nothing else does.

[tjmcmanamen38]

Some other formatting nitpicks:

• avoid the use of C_small and other small variants
• fix the wire over the LED here
• avoid 4 way intersections

• add a green segment between pins and their connections

• fill in rev

• Add dimensions to board in layout (place -> draw dimensions)

Generally make sure to reference Schematic-Conventions.md, some things here we don't do regularly these days but for the most part it is still a very good baseline.

[EDED2314]

I noticed that it was different from what we have done and was wondering if potentially this could result in an issue in the black magic world of RF.

don't think that would make RF a black magic word. But I think there are def some matching issues. Co-planar trace widths to and from antenna matched to 50 ohms should be 0.3487mm. I don't know how they 0.2mm as well, but I think that the arrangement of inductors and caps can be flexed around a little, but the target goal is to get the time a signal is along a trace to be very small.

avoid 4 way intersections

I don't see how else one would implement it without making the schematic messy if we keep all the voltages to one side

The radio chip symbol could be better. The power pins (5,12,13,15,25,28,22,27) could all be combined into one with the others set as invisible and also moved to the top of the symbol as this is power. and gnd can be put to the bottom if we want to keep following this convention.

I think convention is good, but since we are working with the individual chip and not a module, I think we should keep the official library's symbol as is, since there are definitely nuances to power supplies that should not be ignored. Some chips have a lot of power options and it is important to distinguish them/provide flexibility.

Agree with all the other comments :)

[tjmcmanamen38]

With the RF trace imo one of the biggest nonos is the use of vias

[tjmcmanamen38]

wdym about the 4 way intersections it should always be doable.
eg

vs

[tjmcmanamen38]

With the symbol yeah agreed that it's fine to keep as is but technically you can move power pins to the top without having to merge them

[EDED2314]

I implemented the requested changes, lmk if I am missing anything