Yet another PCB design review...

[void_error]

Just asking for experts' opinion.

There will be no soldermask/silkscreen - cheap home made board.

U1 - PIC12F675 (smallest 3-bit up/down counter I could come up with)
U2 - 78L05
U3 - LM358
U4 - UC3843

No component values because I'm currently too lazy to double check everything, I have most of them figured out.





If you're curious about the weird THT - SMD mix it's because that's what I currently have lying around.

[nickm]

Looks decent for a single layer design.  I don't know if you mentioned it in a different thread, but whats the purpose of U3? 

[void_error]

I don't know if you mentioned it in a different thread, but whats the purpose of U3?

U3.2 is a PGA, with gain set by R12-R15 which are binary weighted and handles the current feedback part. It's then OR'd with U3.2 which handles the voltage feedback - limits the output voltage when the load (10W LED) is removed.

[PeterFW]

Just asking for experts' opinion.
(...)
There will be no soldermask/silkscreen - cheap home made board.

I am no expert but i will say somethiny annyway :-P

Depending on your soldering skills i would increase the isolation slightly, without soldermask some of the joints would annoy me when i had to solder them.

Most times i go for a bigger board if i etch them myself just to make it more convenient.

But besides that, looks good.

[tautech]

Just asking for experts' opinion.
(...)
There will be no soldermask/silkscreen - cheap home made board.

I am no expert but i will say somethiny annyway :-P

Depending on your soldering skills i would increase the isolation slightly, without soldermask some of the joints would annoy me when i had to solder them.

Most times i go for a bigger board if i etch them myself just to make it more convenient.

But besides that, looks good.

+1 on isolation and clearances especially for hand soldering. Also consider any possible rework in your layout.
Consider making TH pads oval/rectangular for increased clearances/room for between pad routing.

[T3sl4co1l]

Hmm... given the process (single sided) and spec (basic old fashioned boost, low to moderate power), the power area isn't too bad.  I think that'll work pretty well.  I would still like to see some sort of shorting or jumper or loop across the ground pours, here, and here, and, maybe spanning kind of around here......ehh let me just draw this, alright?



(red = jumper, white = solder, blue = cut)

Also, the strip of ground going off around the right side doesn't do anything, it might as well be chopped off.  Or if you can move the outline so there's ground going around the bottom, so it connects, that'd be good too.

I don't like that the 3844 seems to have no bypass on it, which might be passable for the REF pin but VCC probably really does need it (somewhat contingent on what value gate resistor you've chosen).  You could always tack on a leaded part between pins 6 and 8 to handle that, without needing it indicated on the layout.

Tim

[Ice-Tea]

I would probably keep components away from the bottom of the coil...

[Lizerd]

What about the component holes ? 
Are thy supposed to be that small because you only want to solder on one side ?
seams to be 0.3mm , when it should be more like 0.9-0.8mm

I do not know about the current L1 should be able to handle, but 0.3mm cant handle much

[void_error]

I would probably keep components away from the bottom of the coil...

I'm not sure if I can route those somewhere else but I don't think the coil would affect that part - there are only digital signals there.

What about the component holes ? 
Are thy supposed to be that small because you only want to solder on one side ?
seams to be 0.3mm , when it should be more like 0.9-0.8mm

I do not know about the current L1 should be able to handle, but 0.3mm cant handle much

The 0.3mm 'holes' are just drill bit guides, everything will be drilled by hand to 0.8mm first then enlarged where needed. L1 will carry 1A max.

[Cside]

was this drawn in diptrace?

[void_error]

Yes, that's DipTrace.

Made some tweaks following Tim's suggestions, it should be better now.