Bipolar transistors for SMPS?

In article , Joerg wrote: [...]

There's a job for JT. Do a micro-controller in Supertex's high voltage CMOS process. Just think a PIC that does 60V swings!

--
--
kensmith@rahul.net   forging knowledge
Reply to
Ken Smith
Loading thread data ...

In article , John Larkin wrote: [...]

+----------+-------+ ! ! ! / ! ! \ ! ! / ! ! \ ! ! ! !/e ! +--------! PNP ! !/ !\ !/ ----! NPN +-----! NPN !\e ! !\e ! \ ! ! / ! ! \ ! ! / ! +----------+-------+

This avoids having to deal with a 1.4V e-b drop of a darlington.

If you really want low drop, use a germanium transistor.

--
--
kensmith@rahul.net   forging knowledge
Reply to
Ken Smith

In article , Jim Thompson wrote: [... me ...]

I assume volts per foot remains constant in all directions unless you raise the resistivity of the silicon too, but why grumble. A micro that would (at least) run on a 9V battery would be a nifty thing to have. I'd bet if someone brought one out they'd make litterally dozens of dollars on it.

The poor fellow has a switcher based on some micro (PIC like I think) that is now running on 3V instead of 5V. He needs to redesign the output section to run with a 3V input.

--
--
kensmith@rahul.net   forging knowledge
Reply to
Ken Smith

Hi Ken,

It doesn't have to be big. Once we designed a chip that was running low voltage for RF amps, muxes and so on but it had a high voltage extension. Actually the process claimed 60V just as you had mentioned but in the end we had to keep things below 50V. It was about 2mm by

10mm, not bad considering that it could handle 64 input and 16 output channels. Electro-migration is another issue but this was for a disposable product.

More likely it would be an MSP430, a family that migrates from 5V to

3.6V and less. But the same is true for a lot of logic. Also, there is a desire to run equipment with the least number of cells, typically two.

Regards, Joerg

formatting link

Reply to
Joerg

ElectronDepot website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.