Hi All,
I am repairing a ZX700.5 and the only fault I can find is Q315, that is short. The original is KTC3875GR and I would love to get some recommendations for a substitute. My first preference would be 2SC1632, even though the IC is lower (which looking at the circuit should not be an issue) and the VCE(sat) is slightly higher also. I attached the data sheets for reference.
Thanks all!
Transistor VCEO IC hFE VCE(sat)
KTC3875 50V 0.15A 200-400 Max 0.25V
2SC1623 50V 0.1A 300-400 Max 0.30V
MMBTA06L 80V 0.5A Min 100 Max 0.25V
I am repairing a ZX700.5 and the only fault I can find is Q315, that is short. The original is KTC3875GR and I would love to get some recommendations for a substitute. My first preference would be 2SC1632, even though the IC is lower (which looking at the circuit should not be an issue) and the VCE(sat) is slightly higher also. I attached the data sheets for reference.
Thanks all!
Transistor VCEO IC hFE VCE(sat)
KTC3875 50V 0.15A 200-400 Max 0.25V
2SC1623 50V 0.1A 300-400 Max 0.30V
MMBTA06L 80V 0.5A Min 100 Max 0.25V
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If I remember correctly, I think I used the MMBTA06. The 1623 may be better due to the gain. They likely fail because they have to drain the electrolytic cap when they switch on.
Thank you Don, I am aware that LCSC has stock of these and I may get some to keep on hand in future, but for now I am probably just going to substitute.
If you go with the MPSA06, I think I'd try to trigger the protection by jumping between the positive or negative rail with a 56k resistor to the point marked W on the diagram to confirm that the protection works.
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The MMBTA06 seem to work fine for the moment. Long term testing still to be completed. Thanks again!