fuzzzy
Full Member level 3
pnp transistor relay
Hi,
I've a problem.
I use a pic to switch relay through ULN2003. uln2003 allow current flowing from negative side. I need to switch only one relay allowing current flowing from positive side. I thought to use a PNP transistor to do this.
In my schemathic i've problems: positive relay works good when other negative relays are switched off but when i switch on one of negative relays, positive one stops working.
What is in your opinion the best configuration to do this without problems?
This is my schemathic that doesn't work.
Hi,
I've a problem.
I use a pic to switch relay through ULN2003. uln2003 allow current flowing from negative side. I need to switch only one relay allowing current flowing from positive side. I thought to use a PNP transistor to do this.
In my schemathic i've problems: positive relay works good when other negative relays are switched off but when i switch on one of negative relays, positive one stops working.
What is in your opinion the best configuration to do this without problems?
This is my schemathic that doesn't work.