I designed this circuit to switch on my P channel mosfet because the Vgs will be more than -20 V (maximum Vgs) if I put the traditional design .
Is this circuit correct or can you help me to improve it more?
thank you .
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\$\begingroup\$ Where is the base resistor of your BJT transistor? and you need to add a zener diode in place of R2 to protect the MOSFET from excesif Vgs voltage? \$\endgroup\$– R DjoraneCommented Feb 18, 2016 at 15:41
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\$\begingroup\$ Put a 5k resistor on the Base of Q2 and swap the top and bottom pin of the Q1. You can see in Q1's drawing there is a body diode, all MOSFETs have them, but in this drawing you can see that actually, if you look at the current path, now that diode will always conduct current into your load. \$\endgroup\$– AsmyldofCommented Feb 18, 2016 at 16:06
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\$\begingroup\$ @codo,Asmyldof: Thank you , you are right but my principal goal is to prevent the use of the NPN transistor(Q2). Is it possible ? \$\endgroup\$– Zara ZaraCommented Feb 19, 2016 at 7:32
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Is this circuit correct or can you help me to improve it more?
No it's incorrect - the MOSFET is upside down.
Also the BJT needs a series base resistor.
answered Feb 18, 2016 at 15:43
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\$\begingroup\$ thank you , you are right but my principal goal is to prevent the use of the NPN transistor(Q2). Is it possible ? \$\endgroup\$ Commented Feb 19, 2016 at 7:31
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\$\begingroup\$ Are you changing the basis of your question? Your question states "Is this circuit correct" which I answered then, you said "can you help me to improve it more". Now you appear to be moving the goalposts. \$\endgroup\$– Andy akaCommented Feb 19, 2016 at 11:01
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\$\begingroup\$ I didn't know that you give only one response. I'm sorry . I will talk to someone who gives me responses for more than 1 question. \$\endgroup\$ Commented Feb 19, 2016 at 12:11