The way i understand this chip is that it's a switch, just like any other transistor, but with added features. It has a current output, ie it passes current through it, so it has a max output power, right?
So my questions/concerns about it are as follows:
- Frequency: mostly i see these chips have either 66khz or 130khz operation. So if the transformer is designed to operate with > 66Khz, and the switch isn't, the output on the secondary side will either be too low or will drop out when too much current is drawn from it.
- Max rated power: These chips have a max power rating, I'm assuming 15 watts will be enough, but I don't really know that for sure. Why i'm assuming this is because other boards that I've seen that have a similar build have chips on them rated 15 watts or less.
- Drain voltage: The datasheet for similar chips say it's main voltage rated, but that seems to be the line input, not the drain pin voltage. I measured about 30 Volts on the pin, but not sure that it is what it's supposed to be, also different chips have varying input tolerance on the drain pin, so yeah, issues.
I picked the TOP 242R because it can go up to 132Khz, or operate in 66Khz mode by setting the frequency pin, has a max output of 15w and because it seems to take up to 700v on the drain pin.
I understand there's a lot more to it than this however. There's a lot of data on this device, half of which I have only a vague idea of what it means, The chips seems to fit the bill from my limited understanding of it's main function. The rest I have no idea of, hence jumping in the deep.
I believe this chip is a custom job. It's mode by power integration for sure, but they don't have any data on it. This board comes out of a Miele appliance, and I suspect that power integration made this chip custom for Miele. Like i said, there's a lot of knock off's available from china, but waiting 2 months for a shipment is not what i had in mind.
