ThermalTrak Transistors have been discontinued

Newark provider notified me of this information and the manufacturer Onsemi, I confirm that all models have been discontinued. Although more questions Onsemi did not want to give more information.
Besides the option of Sanken: Does anyone know what other option is there with this technology?
Or does anyone know if this product was purchased by another brand?
 
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I remember Charles Hansen getting mightily pissed off with me for making a business statement about these devices about 3 years ago. I don't know the root cause for ON stopping these devices. Could be a fab closure or transfer, and re-developing an re-qualing are not justified from the business point of view. Or, they just don't sell in high enough volumes - so you prune them from your portfolio. And, if they need lots of tech support or have quality problems . . . kill 'em! How do I know? I was a product line GM for 10 years and part of that time was managing bipolar devices 😀

Temp comp on EF2s is easy, triples are difficult. In this latter case, may I respectfully offer the Bonsai 2 point method here Ovation e-Amp see page 37

Of course, if you want dynamic bias compensation - so bias adjusted with the short term music signal behavior - then you will have to look elsewhere. However, the Thermaltrak devices never offered that anyway so no great loss: class AB is ALIVE AND WELL!!!!!

Nevertheless, RIP Thermaltrak
 
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I just got 5 pairs of this thermaltrak's 2 version samples free from ON semi... and also other trannies like mjl21193/94/95/96....glad i have them for free and maybe placed in good use before they totally gone.
 
I'm not surprised. The TT devices were difficult to apply, as the TC of the diode WRT the tranny were far from matched. Actually, it was a botch job.

Cheers, E.

For On semi, yes. The Sankens have excellent matching of tempco between the diode (strings) and the power dies. I believe these still are available, e.g. from Profusion. STD03N & P. But they are Darlingtons...

jan
 
I dont understand why darlingtons are vilified ,
my prefered devices are indeed lateral fets but (Sanken) darlingtons
follow on the list with discrete double EF being at the end.

Sure that such devices mandate a little more than a lousy temp
compensation.
 
Thanks for the heads up. Methinks it's time to buy a hundred of each to help Mouser dispose of their existing final stock. The ones that don't get used, can always be sold at auction (whatever replaces eBay in 2021) for a tidy profit. Including an above market Compound Annual Growth Rate.
 
did anything commercial actually use these? I guess they are useless if the diode doesnt reliably track, you might as well just use a TO92/TO126 device bolted to the heatsink in that case. This was the market appeal of the sanken SAP devices after all.