I'm seriously burned out "CTO" (small company 20 people, 4 developers).
Should I tell my CEO/CFO exactly that?
Should I tell them, I can't take it anymore, please help me.

Next month we'll have a fund raising opportunity.
I'm afraid it will sound like a blackmail.
I'm afraid they will think, ok, he's burned out, let find somebody else.

On the other side, if I take the risk myself, without telling anyone, I could explode and I'll be on my own.

What do you think it's the best approach?

Tell them.

If you need some time off, take some time off.
Your health is always more important than your job. You can get a different job, if you need to, but getting rid of health problems is not so easy.

kill them.
you're a @killerdev after all ¯\_(ツ)_/¯

Tell them. It’s better than costing them body bags...

get professional help too!

@burningcandle yes!!! but what do you think if I say: "look I'm burned out, if you don't help me the next meeting with the investors I'll start to scream and tell the truth about security, licenses whatever, bugs, resources and that I'll leave without notice nor passing knowledge immediately" in front of them.

@TobiSGD @NoMad I'm 57, my tech skills are outdated and I'm sure my salary will be 1/3 if I'm lucky

@Coffe2Code I have recurrent fantasies about that. About sticking sharp pencils in their eyes. Scissors in their throats. It seems very easy. Zac.

Or smash laptop on heads.

Very often. fantasies

@heyheni yes, I'd like to

You are responsible for the lives of 20 people.
It's no problem to burn out. The problem is that you destroy the company if you are not getting any help.
The first step is to be true to your partners.

@burningcandle It seems to me very good...if somebody would do that with me I'll appreciate it greatly. But I'm afraid they will think, "oh this shit guy is a problem, he is putting our money in danger, he cant handle the situation, nor the pressure, let find somebody else"

So my stress will actually increase greatly. I'll be scared

I've been there too. Not as a CTO but lead dev though.
I didn't tell anyone. After a while I lost my drive, my productivity fell. Some days I didn't write any line of code, just wandering on the web trying to restore my energy.
Fortunately the company had time to grow (~30 devs), so the impact was low. But still, I've put the company at risk then. And my health too.

Anyone who had lived it will be thankful that you tell them. If they don't, that mean they don't give a shit about you and underestimate your value. In that case, it's a no brainer: leave.

TL;DR: Tell them. It won't be pleasant, but it's the right thing to do.

Tell them. But also tell them how you'd like to move forward (ex. An additional dev team with an own tech lead or a PM, so you can focus more on the dev side, etc.) Just talk to them on how to resolve this situation.

Honestly just tell them and ask for a break

If money is more important than your health, I would revise priority