the Issue where the VPS voltage is 0-10.5V if a load is present prior to turning on the circuit Q2 wont turn on fully the voltage at the gate is 11.9V instead of 6.2V is its on

• meaning if a load is connected at the VPS net prior to turning on ps is connected it wont recive the 12V
• If no load is preset, when circuit is on VPS+ will be 12v, Q2 is turned on as expected at that moment load is turned on the circuit will work just fine .

il appriciate any help and explination on why it occures.
Thank you in advance

 

the Issue where the VPS voltage is 0-10.5V if a load is present prior to turning on the circuit Q2 wont turn on fully the voltage at the gate is 11.9V instead of 6.2V is its on

• meaning if a load is connected at the VPS net prior to turning on ps is connected it wont recive the 12V
• If no load is preset, when circuit is on VPS+ will be 12v, Q2 is turned on as expected at that moment load is turned on the circuit will work just fine .

il appriciate any help and explination on why it occures.
Thank you in advance

If you are having a problem with too much inrush current, use a Thermistor to limit it. Size it appropriately, of course. That's what they are for.

 

Good Lord ,
what is all that circuitry for?

 

the circuit it design for inrush current + to intruduce a dealy of couple ms between the input to a PS block . the ps (s24se) it self is curretly not connetected and i currected a demi load insteac, if i start with about 5k resistor and lowering the resistance the circuit works fine but with low load i get the issue only at the startup.

 

Appears the VPS is the problem.
What is the resistance of the load when the problem starts to happen?

 

aproximetly 3-5k, the issue is only on startup, if i turn off load tunr on the circuit then turn on the load (manualy ) after 2 second it works just fine, is the issue could be related to the Q2 gate voltage / current ?

 

I'm not sure, the whole schematic is confusing and most of it is probably not needed.
It certainly doesn't appear to be a current problem more of a design problem.
What exactly is the purpose of Q1 and Q2 and Rv1?
You show Vin+ and VPS+..... ???
What is the load on Q2 just Q3,Q4 and Q5 circuits?
What exactly is the Vin+ voltage, what value?

 

Why are you trimming the output voltage down so far?

ak