I am repairing an AB systems 900A amp that uses TIP122/127 Darlingtons as drivers. From what i am reading the TIP127 is a high failure rate part which explains why the three dead boards i have on hand all have then 127 removed...
Can anyone recommend a suitable replacement?
Zc
Can anyone recommend a suitable replacement?
Zc
I'd be tempted to try the TIP147, they seem quite robust and should work in the same position - 100volt darlington device like the 127
BDX33C/BDX34C - a 100V, 10A darlington that's multiple sourced by ON Semi, ST, Philips and maybe Infineon.
I have the TIP147's in stock but they are a larger case size. It will take some magic to get them to work but it's worth a shot. I will look into the BDX parts thanks LG
Hi,
Might the high failure rate be caused by excessive VCE or excessive dissipation over the device? In both cases I think TIP 107 will not help.
Regards,
I am not exactly sure why they fail. either they fail and take out other parts, or other parts fail and take out the 127's every time. Probably when an output device fails it takes out the 127 i dunno...but the 122 never dies. so i thought i would try an alternate and see what happens.
Zc
Zc
Interestingly TIP107 has higher current gain, better DC safe operating area but worse pulsed SOA. So for audio applications it may actually help.
Internal resistors are higher value on TIP107, though.
Internal resistors are higher value on TIP107, though.
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