I designed below circuit to provide 45V/200mA for a LED ceiling lamp.
After some tests, I made a stripboard version with the same components but cannot work normally... 1. MC34063 became very hot after powering up. (~5sec) 2. TIP31C became cooler than breadboard version (touchable). 3. Output dropped to ~39V.
I guess the driver/output transistors inside MC34063 wasted too much energy and generated too much hot. Should I lower the value of input resistor of TIP31C or do something else?
By the way, I tried to replace the inductor with netshop's product during breadboard version test and found the circuit's performance decreased (They have the same rating 470uH/3A). Origin inductor's core is yellow and netshop one looks like: I can't explain why. Can anyone explain it for me?