After many silly mistakes over a period of two days I got the following circuit to work. This is the second time I worked with switching regulators. I am happy that I succeeded, well at least partially.
Circuit is from from the data sheet of XLSEMI, XL6009 ic.
I still havent connected any load.
Now I realize it behaves wierd when I touch it with my bare hands or even with the help of any metallic conductor held in my palm. I have marked the red circles where I touched and the output swings wildly between 2V to 90V+, no electrical shock though, the input voltage was just 13Vdc but I find that even this ip voltage fluctuates. I can see this because I have connected 2 multimeters at input and output points. When I remove the contact the voltages come back to the original values. The points marked blue are areas where I touched but produces no such change. The voltages are steady in this case. I also see no heating issues anywhere.
My layout and soldering is very amateurish , I have basically reproduced the circuit diagram on a perforated veroboard but tried to keep components as close as possible.
Do you think this is a known problem with such regulator ICs ? My LM317 implementations never behaved like this !
Do you think excessive heat while desoldering this ic from another PCB might have damaged it ?
Do you think I can ignore this problem because this circuit is going to be working in an isolated box and wont be touched ? The voltages are steady when touched any where else apart from the red areas marked on the circuit diagram.
If this is a serious issue and needs to be corrected before I connect it to any precious load, please give a clue as to how to rectify this. It will be helpful of you if you post any links to reading material to upgrade my knowledge regarding this issue.
Thanks for your time
EDIT : I am sorry, I forgot to add an important point, The recommended inductance is 47uH. I wound till 90uH, was too lazy to unwind, so its running with higher inductance. Is this the cause of instability ?
Circuit is from from the data sheet of XLSEMI, XL6009 ic.
I still havent connected any load.
Now I realize it behaves wierd when I touch it with my bare hands or even with the help of any metallic conductor held in my palm. I have marked the red circles where I touched and the output swings wildly between 2V to 90V+, no electrical shock though, the input voltage was just 13Vdc but I find that even this ip voltage fluctuates. I can see this because I have connected 2 multimeters at input and output points. When I remove the contact the voltages come back to the original values. The points marked blue are areas where I touched but produces no such change. The voltages are steady in this case. I also see no heating issues anywhere.
My layout and soldering is very amateurish , I have basically reproduced the circuit diagram on a perforated veroboard but tried to keep components as close as possible.
Do you think this is a known problem with such regulator ICs ? My LM317 implementations never behaved like this !
Do you think excessive heat while desoldering this ic from another PCB might have damaged it ?
Do you think I can ignore this problem because this circuit is going to be working in an isolated box and wont be touched ? The voltages are steady when touched any where else apart from the red areas marked on the circuit diagram.
If this is a serious issue and needs to be corrected before I connect it to any precious load, please give a clue as to how to rectify this. It will be helpful of you if you post any links to reading material to upgrade my knowledge regarding this issue.
Thanks for your time
EDIT : I am sorry, I forgot to add an important point, The recommended inductance is 47uH. I wound till 90uH, was too lazy to unwind, so its running with higher inductance. Is this the cause of instability ?
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