Hello,
I am looking for some help with an over voltage protection circuit without using a crowbar clamping circuit or using anything too elaborate. I have attached a picture of the schematic for anyone who is willing to help.
I have a current mirror circuit where I am setting the reference current as 100μA. The DUT in this circuit is D1 and it must have 100μA through it. The device I am trying to protect is Q1, where VCE max is 24V. The transistor part number is CA3046 (specially picked for my application).
The nominal clamping voltage of the DUT (D1) is 390V. I am trying to protect the transistor (Q1) in case the DUT is somehow shorted. If it is shorted the high voltage will then appear across Q1.
I have only shown 1 DUT in my picture, but in my actual application there will be 25 DUTs using these transistors to mirror my reference current.
Any help is greatly appreciated.
If I did something that goes against this forum please forgive me as I am a new member (I did read the rules and regulations though).
Thanks again.
I am looking for some help with an over voltage protection circuit without using a crowbar clamping circuit or using anything too elaborate. I have attached a picture of the schematic for anyone who is willing to help.
I have a current mirror circuit where I am setting the reference current as 100μA. The DUT in this circuit is D1 and it must have 100μA through it. The device I am trying to protect is Q1, where VCE max is 24V. The transistor part number is CA3046 (specially picked for my application).
The nominal clamping voltage of the DUT (D1) is 390V. I am trying to protect the transistor (Q1) in case the DUT is somehow shorted. If it is shorted the high voltage will then appear across Q1.
I have only shown 1 DUT in my picture, but in my actual application there will be 25 DUTs using these transistors to mirror my reference current.
Any help is greatly appreciated.
If I did something that goes against this forum please forgive me as I am a new member (I did read the rules and regulations though).
Thanks again.
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