Single-Board Universal Module

do you have an inductor in mind? Most of the 0603 2.2uH inductors I looked at either had very low current ratings, or a very low saturation current which I think would reduce the effectiveness of the filter. I can probably fit a 0805 inductor if I move things around.

How about this (updates are checked in if you want to look at it in eagle):



I used the same 0805 2.2uH inductor I use in the previous stage. I mounted them perpendicular. I'm not sure if coupling will be an issue since they should have constant current.

Here is the board with the band-pass filter:



Everything is checked in

Should I be concerned with fragmenting the 3.3V plane too much? when I go crazy with ground vias, it tends to break up the 3.3V plane. I've tried to keep a good via density while still ensuring a robust power plane. But maybe I'm focusing on the wrong things.

I fixed the BPF:

I assembled one of the 0.9.3 boards today. This still has the LDO and since I didn't have any other Shottkey diodes, I just reduced the pulldown resistor to 200ohms. This is the 3rd board I've assembled, and I'm getting a little faster, but still hate doing them. The 0.9.3 design has the compressed RF layout to fit under the shield (though e I didn't actually install the shield on this build). I had no issues with tombstoning so I guess the via placement is ok. I did forget to remove the cream-layer around the shield from the stencil, so I needed to scrape the solder paste off which didn't go so well. I still need to test it out, but hopefully this next iteration (with the DC/DC converter) will be the final one.

Edit:
FYI, the reason I snake the PA control lines around the PA rather than going straight alongside YY_1 is that there isn't quite enough room for the routes between the pad vias and the resonators, and layout is so tight, I don't want to try moving any components. They are low frequency digital lines, so snaking around shouldn't cause any issues even if it isn't pretty.

Well, on my 3rd board, the nrf chip doesn't output any RF signal. I'm at a loss, since the solder joints all look fine, and it responds to SPI traffic. It also toggles the PAEN pin as if it is transmitting, but there is no rf output. Even if I probe right at the chip pin.

Possibilities:
1) the solder joints aren't ok somewhere, and I just can't see it
2) the NRF chip is bad
3) I installed the wrong component somewhere and am loading down the RF pin(s)
4) ???

The oscillator is fine (which it would need to be for the PA_EN to flip). I don't have equipment to pick up a high-frequency signal (my rf explorer can only pick up 2.4-2.5GHz range, and I haven't been able to find a trace of that on the board with nrf enabled so far). Pins 12/13 are at 1.88V (just as they are on the working module). In fact all the pins seem to have similar DC voltage characteristics to the working module.

Can it be bad inductance (shorted) on the path from VDD_PA (11) pin to ANT1 and ANT2 pins?