SMD Adventures

Initially I had put these bridge-pads on there to select which pins are + and - and connect capacitors to them. Today I used this board with an MCP1804-SOP23-5 voltage regulator. I had everything plugged in and was in need of another GND pin. Not just the one going to the chip, bot one going to the load. Thanks to these jumpers I could use the unused pin #5 (top row in the middle) and just bridge it to GND. I need more of these little moments!

I used my good paste-flux and this dirty little pin still didn't take the solder. Thankfully the board is very simple and with a bit of logic and beeping it was fixed quickly.

This board was giving strange test results. There was crosstalk between two inputs. Now I know why.

The right board looks really nice. I've already built it. However it was a PAIN to assemble by hand. Tiny 0603 parts too close together. It took me ages to complete. Too much effort to be fun if repeated. The left board still comes with the LEDS. They are the whole point of this board's existence. The tiny resistors however were replaced with easily manageable 1206 resistor packs. Assembling 4 large parts vs. 16 tiny parts with no room to move. Lesson learned.

Forgot to get the quartz, diode footprint doesn't quite match, still missing the programming adapter board... the usual stuff.

It wasn't cheap, but it was super easy to dispense at room temperature.

An air-tight container with some desiccant in the plug that just so happens to be longer than a certain syringe full of solder paste which needs to be put into my fridge. Hmmmm...

I stuffed in some paper to pad the bottom so the syringe doesn't rattle.

I guess I won't mistake it for something edible, but solder paste kind of looks like anchovy paste (which I hate).

I wouldn't know what to do without that stuff ;-)

The DIM input of the PT4115 is very susceptible to over-voltage - even from a high-impedance source (skin resistance, bridging DIM to VCC).

That method worked pretty well with a board that had top and bottom copper pour and quite a lot thermal vias.

1k dropper resistor + 5V1 Zener diode BZX84C5V1.

The result is pretty good. I think I could use an even smaller tool (spear-point drill). Using sub-1mm fluted end-mills can get a bit tricky, especially if they're not of the short and stubby kind. They break quite easily - and cost a lot.