i think most of us familiar with L10 amplifier see also schematic on picture
I have one application that I have primary rails of regulated supply to feed the first stages lets say up to the drivers and a lower rail very beefy to feed the output
Can one quick simulate for what is the maximum voltage to feed the input stage ?
I have one application that I have primary rails of regulated supply to feed the first stages lets say up to the drivers and a lower rail very beefy to feed the output
Can one quick simulate for what is the maximum voltage to feed the input stage ?
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Ironically, this one cannot be determined by simulation (which rarely represents breakdown voltage accurately) but requires old-fashioned studying of datasheets instead. I think the 2SD667/2SB647 are the bottleneck, being Vceo = 80 V parts and having to swing almost rail to rail. So roughly +/- 40 V max, or +/-50 for 667A/647A. In the latter case a fault condition with the output pulled to V+ may still destroy Q6 (a 65 V part) and/or C4.
Vceo max. may vary between manufacturers. Some examples of 2SD667A/B647A appear to use the same die as 2SD669A/2SB649A (as for example, do BD139/BC639). http://www.secosgmbh.com/datasheet/products/SSMPTransistor/TO-92MOD/2SD667A.pdf
There are even standard T092 versions of 2SD669/B649 to add to the confusion. Even with datasheets, I would test the breakdown voltage before fitting.
There are even standard T092 versions of 2SD669/B649 to add to the confusion. Even with datasheets, I would test the breakdown voltage before fitting.
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