i made a 4 layer board layout a 100khx esr meter design

[sphinx]

this a project from nuts and volts magazine 100khz capacitor esr meter

it is my first time i am fiddling with 4 layer board using top layer as signal it seemed enough while routing it
so i chosed to make the other layers as +5v -5v and a ground layer i am looking for input on the idea itself
and if i made a bad/good decision and if the routing istelf is ok, maybe the order of s.c. planes are in a good
order

one thing that could be changed is to use smaller footprint voltage regulators like SOT-223-4 or TO-252-3

[bobcat1]

this a project from nuts and volts magazine 100khz capacitor esr meter

it is my first time i am fiddling with 4 layer board using top layer as signal it seemed enough while routing it
so i chosed to make the other layers as +5v -5v and a ground layer i am looking for input on the idea itself
and if i made a bad/good decision and if the routing istelf is ok, maybe the order of s.c. planes are in a good
order

one thing that could be changed is to use smaller footprint voltage regulators like SOT-223-4 or TO-252-3

Hi
You should add a PDF schematic for anyone who don't have install the software

[sphinx]

info/docs are in the file above

here is pdf wirg schematics and layout
layer 1 = signal
layer 2 = +5v
layer 3 = -5v
layer 4 = gnd

layout is sorta straight forward
from left to rirght
power input
oscillator
capacitor test
panel output

p.s. every project i make i have a folder with documentation and other extra info like compoent exchange or other info

a schematic was already in the doc/info  folder

[digitalmg]

For 4-Layer Stackup.
Very common, but not ideal Stackup
Top layer 1 - High Speed Signals
      layer 2 - GND
      layer 3 - Power Plane
      layer 4 - Low Speed Signals

Recommended
Top layer 1 - Signals/Power
      layer 2 - GND
      layer 3 - GND
      layer 4 - Signals/Power
Why? there is a lot to explain, watch a webinar that explains why:
https://go.teledynelecroy.com/l/48392/2022-05-12/8g9wzc?&utm_source=si-academy&utm_medium=banner-ad&utm_campaign=22-06-14-bogatin-3-design-tricks

I think you should change layer 2 to be gnd. 

[Sideshow Bob]

For 4-Layer Stackup.
Very common, but not ideal Stackup
Top layer 1 - High Speed Signals
      layer 2 - GND
      layer 3 - Power Plane
      layer 4 - Low Speed Signals

Recommended
Top layer 1 - Signals/Power
      layer 2 - GND
      layer 3 - GND
      layer 4 - Signals/Power
Why? there is a lot to explain, watch a webinar that explains why:
https://go.teledynelecroy.com/l/48392/2022-05-12/8g9wzc?&utm_source=si-academy&utm_medium=banner-ad&utm_campaign=22-06-14-bogatin-3-design-tricks

I think you should change layer 2 to be gnd. 

I think in this particular design with 100Khz signals. It do not matter much much. In fact 4 layers is kind of overkill. Not that it will do any harm though. 

[bigtoy]

Agreed - 4 layers won't really help anything, but it won't hurt either (well, aside from the hurt wallet due to the more expensive PCB).

Just a warning that if changing to a smaller voltage regular package, first make sure you know its power dissipation. Sometimes a larger part is required for dissipating the heat.

[sphinx]

yes one has to think about the thermal aspect of a smaller package, i was also thinking about the price as well
if a smaller package was more expensive, i wouldnt choose it