After viewing the two plots in post #43, I am reminded of the wisdom of my very conservative first boss: Qualify Your Vendors! Then keep re-qualifying!
This was a guy who insisted on writing seven (7) copies of a mask database tape during IC tape-out. Then send three of them to the mask shop. Now those lazy oafs in the mask shop can't put your job aside and party all day, claiming "the tape won't read."
This was a guy who insisted on writing seven (7) copies of a mask database tape during IC tape-out. Then send three of them to the mask shop. Now those lazy oafs in the mask shop can't put your job aside and party all day, claiming "the tape won't read."
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Hi stormsonic and Mark,
Tks for the very useful info.
What about BC639/40? http://www.onsemi.com/pub_link/Collateral/BC635-D.PDF
Could be a good choice?
Regards,
LTSPICE IV supports VBIC, there are a couple of threads here on incorporating quasi-saturation.
In some sense, but the 639/640 from ONSemi seems to be different from the ones of other brands.
But, even considering the same brand, there are different parameters, maybe due to the metallic tab on BD´s.
Regards,
Just wondering about 2SC3332 going at a reduced price at local supplier - quite cheap
http://docs-asia.electrocomponents.com/webdocs/127c/0900766b8127c810.pdf - may not be a best fit current wise - but any possible audio uses?
http://docs-asia.electrocomponents.com/webdocs/127c/0900766b8127c810.pdf - may not be a best fit current wise - but any possible audio uses?
I buy from RS Components - a source for genuine parts - with branches here and other countries. They list these as made by On Semiconductor with the hFE classification of T =200 to 400 with IC of 100 mA. - 80 minimum at IC of 10 mA with the lowest hFE rank R type.
There is an element of Hmm about the parameters - I will put in on my short list of possibilities.
I tried using VBIC, but I couldn't get any better results than just using the standard model with it's quasi-saturation additions.
Hi Mark,
This does indeed look like a nice device. I'll have to look up its datasheet and see if it has a complement and what the ft is.
BTW, I noticed that the Locky curve tracer was used for this plot. Did you do the test that produced these curves? I bought a Locky curve tracer over a year ago, but never had the time to set it up and use it. Was it easy to get it up (assuming this was from yours)?
Cheers,
Bob
Yes the LockyZ curve tracer is easy to set up, once somebody tells you the magical secret:
BD437's complement transistors seem to be BD438 and BD442, neither of which have a large Early voltage. Measured VA is 87 volts, pew.
When it comes time to install the USB driver software, right click on the installer and select "Run As Administrator". If you fail to do this, misery awaits you. The drivers will appear to install but they won't work properly and you will mutter many bad words from a sailor vocabulary.
Handle your curve tracer gently, LockyZ is not currently selling new ones or repairing old ones.BD437's complement transistors seem to be BD438 and BD442, neither of which have a large Early voltage. Measured VA is 87 volts, pew.
Attachments
Stuartmp, your question is now here:
http://www.diyaudio.com/forums/solid-state/171159-bob-cordells-power-amplifier-book.html#post5105130