Ultrasonic Pest-Repellent device not working PNP Transistor heating up H-Bridge

Thread Starter

Alan Porco

Joined Nov 23, 2018
2
Hi, this is my first time posting!
I'm making my own Ultrasonic Pest-Repellent at home but when I plug the board in Q3 which is a TIP29C PNP Tansistor it heats up really fast and the sound that i'm getting is not the right one, the transistor is located inside a H-Bridge that recieves a the signal from a CD4013 Flip-Flop.
I'll attach the circuit's schematic circuit so you can see and tell me what you think is going on in the circuit.
DC +12V.
PD: I used U4:B to ground the second clock, second set and second reset.
Schematic attatched here ↓↓↓↓

Captura.PNG
 

Alec_t

Joined Sep 17, 2013
11,517
Welcome to AAC!
I used U4:B to ground the second clock, second set and second reset.
I'm not clear what you mean by that, but if U4b isn't being used all its inputs (including D) should be grounded or the IC could misbehave.
What load is the H-bridge driving?
 

Thread Starter

Alan Porco

Joined Nov 23, 2018
2
Welcome to AAC!

I'm not clear what you mean by that, but if U4b isn't being used all its inputs (including D) should be grounded or the IC could misbehave.
What load is the H-bridge driving?
The H-bridge drives 1V aproximately but i'm not clear if this is the right load eitherway, i'm really lost right now.
Before R7 I measure less voltage than after it, I dont get what's going on, maybe the TIP29C is missbehaving in some way or D grounded may fix the problem. I'm totally lost rn. Voltage in J2 Should be 12V and measurement gives me 0,8V aprox. instead, what would that mean?
 
Top