AmyAlice: DC filter for SMPS, using 2 feedthru capacitors + SMD assembly. max 3A & max 48V

[Vunce]

91% not the sissy 70%

 

[Mark Johnson]

ahem.

 

[Vunce]

WooHoo!
Super strength, even better.

 

[Skip Pack]

I've never seen any isopropyl above 90% in a store but I bought a quart of the 99% online a couple of years ago.

 

[DPH]

Soaking your PCB's in a covered container with enough IPA to cover the PCB is the lazy person's way. Then an old junky toothbrush to scrub it all off does the trick. (Rinse well, keep scrubbing with toothbrush)


Thanks, Mark for this design! I hope there's no issue if I poach the circuit and park it on the power input of some of my future boards?

Daniel

 

[Hicoco]

 

[bohrok2610]

For gleaming-clean PCBs use ultrasonic cleaner with this:
https://www.amazon.de/-/en/Oregon-Ultrasonic-Cleaning-Concentrate-Bottle/dp/B07X5NK3Z6

Some baking time in oven probably useful after cleaning to remove moisture. For best results first remove most flux with IPA and toothbrush.

 

[Skip Pack]

Here's the pic of the one I soldered yesterday.

Scrubbed, but a tiny bit of flux left. Solder is smooth -- does that indicate too much heat possibly?

Thanks, Skip

 

[zergxia]

I tested the discrete component filter last night and it worked great .

Purple is the input，Yellow is the output.

 

[Mark Johnson]

Please feel free to call your creation any name you like, as long as it's NOT "AmyAlice". AmyAlice includes no R050 resistor and no 1K resistor and no 0.1uF capacitor and CERTAINLY no toroidal common mode choke. AmyAlice has two inductors per rail (not four). AmyAlice includes a TVS, missing from yours. Whatever that circuit in #69 happens to be, it certainly isn't AmyAlice.


_

 

[zergxia]

Yes, it's not "AmyAlice", I borrowed your circuit and made some modifications with the components I already had.

Thanks for sharing

 

[BrianGasberg]

Working perfectly - thanks Mark

 

[carlpsyd]

Thanks for a great intro into SMT. I've built 3 with more on the horizon, when parts arrive from Mouser.

Replaced 2 P089ZB (original SMPS) and the deference in sound is pretty stunning. Most notably in the ACA Mini amp. The sound dynamics increased beyond what I could have imagined possible.

Appreciate all you're education bits regarding SMT tech.

this is t he first board that is setup for the negative side of a power supply source. Waiting to build the positive side of the rail.

 

[Mark Johnson]

Congratulations @carlpsyd , glad you tried SMD and succeeded! Thanks for the listening evaluations as well.

I think you may want to double check whether you remembered to rotate TVS Diode "D1" on the Negative Supply Filter PCB shown in post #73. The diagram showing the proper rotations is attached to post #31.

 

[carlpsyd]

Thanks for the heads up.

Double checked with a meter and got it going in the correct direction for negative supply filtering.

 

[skibum]

What do the 750R resistors in parallel with the 10uH inductors do?

Thanks!

 

[Mark Johnson]

Do a Forum Search for all postings containing the character string Rcalmdown

and read the ones written in November 2020.

 

[Solve]

Is it any recomended max length for the cables?

 

[Skylar88]

How much voltage drop can I expect at 200mA with 5V supply?

 

[schultzsch]

~40mV