Mithun_K_Das
Advanced Member level 3
- Joined
- Apr 24, 2010
- Messages
- 899
- Helped
- 24
- Reputation
- 48
- Reaction score
- 26
- Trophy points
- 1,318
- Location
- Dhaka, Bangladesh, Bangladesh
- Activity points
- 8,254
I was trying to make a DC/DC boost converter with MC34063A. It is a good IC for the purpose but its not working well.
Having a lots of trouble.
Here is the PCB diagram:
And the circuit diagram is here:
The problems are:
* Its taking high current at startup, frequently MOSFETs blows away.
* If current is reduced from the supply and then controlling the current tuning current controlling VR, it genaretes 30-35V[unstable]. But whenever load is applied, it become short again.
* Genareting lots of heat in Fets and Inductors.
I tried with changing inductors by 47uH,100uH,120uH,220uH. Timing cap: 222,102,104,103. Diodes: UF5408,HER308,SR560. Fets: IRF3205, 75n75, IRFZ44N,
no improvement. All similar problem. :-(
Need help.
Having a lots of trouble.
Here is the PCB diagram:
And the circuit diagram is here:
The problems are:
* Its taking high current at startup, frequently MOSFETs blows away.
* If current is reduced from the supply and then controlling the current tuning current controlling VR, it genaretes 30-35V[unstable]. But whenever load is applied, it become short again.
* Genareting lots of heat in Fets and Inductors.
I tried with changing inductors by 47uH,100uH,120uH,220uH. Timing cap: 222,102,104,103. Diodes: UF5408,HER308,SR560. Fets: IRF3205, 75n75, IRFZ44N,
no improvement. All similar problem. :-(
Need help.