I'm building "lab" (read: regulated) power supply. I've routed the board and I'm thinking if it has any chance to work. Here are schematics. The board:

enter image description here

My main concerns:

  1. IC3 is ST1S14 - used here as up to 1A buck converter. IC15 is AZ34063 - used as <200mA buck converter. Are these routed like they should be? I've read handful of switch mode converters routing tips, but some of them were contradicting each other like: "keep everything close" and "keep feedback as far from inductor as possible". While both of these seem reasonable, both of them cannot be satisfied at once. I also tried to find reference designs of these ICs, without success. In ST1S14 application schematic (on first page) there is "small signal" ground connected to common point below output capacitor and I tried to implement this in my design. Is it what author of the datasheet meant? Is this done right in my case?
  2. Can proximity of two dc-dc converters cause any trouble? What can I do to minimize to interference if there is any, apart from moving the converters farther apart?
  3. Will converters cause any problems to some other board part?
  4. There are plenty of ground plane discontinuities in the lower part of the board. Can that affect analog circuitry in the upper side?

Also let me know if you see any other flaws.

If this helps I can hapily provide you with whole eagle project.

  • \$\begingroup\$ From a quick glance, doesn't seem that the plane(s) are properly laid out or very well connected. (which can be quite bad for switching power supplies) \$\endgroup\$ – Wesley Lee Dec 8 '17 at 22:51
  • \$\begingroup\$ You mean the top layer planes? What should I improve? \$\endgroup\$ – ja2142 Dec 8 '17 at 22:53
  • \$\begingroup\$ You have too many unnecessary cuts on the planes. Try to have as much of a continuous plane as possible (the bottom one). On the SMPS part, more vias closer to the caps and diodes will help them have a less inductive path to ground. Google "SMPS layout App note", there are great references out there. Here are a few: 1, 2, 3 \$\endgroup\$ – Wesley Lee Dec 8 '17 at 23:09

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