| Electronics > Projects, Designs, and Technical Stuff |
| Power bipolar transistor die -> parallel??? |
| (1/5) > >> |
| Noopy:
Hi all, I did some pictures of a Sanken-Transistor (2SC2922): https://www.richis-lab.de/2SC2922.htm It seems that the transistor consists of a lot of small transistors connected in parallel: But how does this work? Paralleling bipolar transistors (without resistors at the emitters) leads to more current for the hottest transistor and so to failure of this transistor. You know what I mean. Can anyone explain why the engineers were able to connect these transistors in parallel? Or is there a misunderstanding on my side? Greeting, Richard |
| nctnico:
Since the transistors are on the same die they are largely the same. However hotspots will develop and there is a distinct difference between transistors made for switching and audio applications. The former have a very small DC SOA. |
| exe:
My guess is they rely on 1) good match between smaller bjts because they are on the same die 2) thermal coupling between bjts. |
| m3vuv:
rf power transistors have been made this way for years,a lot of times they dont totaly fail just several elements,ie transistors on the die,leading to reduced output. |
| CatalinaWOW:
I don't know about this one, but some have had small emitter resistors included on the die. But as far as I know most depend primarily on the similarity of all of these transistors that are very close on the same die. |
| Navigation |
| Message Index |
| Next page |