Paralleling two or more TO-220 devices is more convenient than using the same single die in a bigger package.
What about matching for paralleled devices? Or is that not so much a concern with devices from the same production batch (assuming they are from the same batch)?
In my experience, matching is not a requirement for switching applications. Also, when transformers and very high currents are involved, splitting the main transformer in two or more smaller ones with their primaries or secondaries connected in series allows to achieve perfect current sharing. But then again, this transistor can handle 75A continuous dissipating 25W or less, which is a manageable figure for a TO-220 case. Do you need more current?
not really, BUT an I(d) of 75A, and an Rds(on) of just mW is pretty cool, pardon the pun. 😉 I encountered the splitting of the transformer into smaller, manageable sizes, and then putting their secondaries in series when I opened up a friend's 2.5kW Inverter. Two sets of four 400W SMPS ferrites with their secondaries in series for about 165VDC for the DC-AC conversion stage. Pretty cool concept.
splitting windings,
so are both the primaries and secondaries in series or primaries OR secondaries in series?
so are both the primaries and secondaries in series or primaries OR secondaries in series?
The primaries are in parallel. Each center-tap push-pull primary is driven from its own pair of very-low Rds(on) N-Ch MOSFETS, all driven by one TL-494. These stages are fed from the same 200A 12V bus. The four 42V secondaries are in simple series, generating a DC voltage after rectification of ~165-170VDC. There are 8 primaries, and 8 secondaries. Four of them are "seriesed" for the HVDC section, and paralleled with the other four "seriesed" rectified secondaries.
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