Npn transistor KTC3964

Semiconductor Discrete Semiconductor Products
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I’m new to this but I’m working on a Denon avr-x4500h trying to change the power transistors on the 4 channel amp and 5 channel amp board that is the transistors that is attached to the radiators. I have a few channels burned out on the 4 channel amp board so I disconnected it so I still can use my receiver until I get all my parts in to fix it but I need #4 of the KTC3964 NPN transistors I need help trying to find this part. So I can make 1 order any help will very much appreciated thanks and have a blessed day.

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Hello @ns2_1982

Welcome to the TechForum

I was not able to find a direct replacement for KTC3964 on our site.

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Ok thank you I appreciate it. I looked but I couldn’t find it either.

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Hello @ns2_1982,

If you are not able to locate the KTC3964, you may be able to use a BD139:

Unfortunately, I cannot guarantee success as this medium-sized transistor serves as part of the amplifier thermal stability circuitry. It is bolted to the heatsink so that it will be at the same temperature as the larger output transistors. It forms a feedback loop to reduce the output transistor conduction as the system heats up. Stated another way, it prevents a thermal runaway condition.

For additional information please refer to:

Best wishes,

APDahlen

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Thank you Im hoping I can find the same one the receiver uses but if I have to at least I might have something to work with. Thanks again for looking into thus situation for me.