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Brians256 · 08-02-2003, 04:03 PM

Thanks murray13! I appreciate someone answering me with enough knowledge to tell me what I'm up against.

I can definitely say that the MOSFETs are a DPAK of some sort. I've been reading up on the datasheet for the Intersil DC-DC converter control chip HIP6302 to learn some of what THEY think is important in selecting components.

What I was hoping to find was enough specs on the existing parts to find an alternative with similar but improved parameters. For example, with the improved processes available today, I should be able to get a MOSFET with a similar gate capacitance, switching frequency, and current capability with a lower RDson. Maybe I could even lower both RDSon and gate capacitance. After all, I can buy a couple of $5-10 MOSFET where a mobo manufacturer would want to stick with $1 or even cheaper MOSFETs. I've been reading all the marketing fluff coming out of IRF and similar manufacturers all proud of their trench FETs and so on. So, they must be making things better these days, right?

Also, you should be able to do the same thing with the inductors and capacitors. Manufacturers REALLY like to buy cheap stuff. I know that I should be able to buy a pair of low ESR caps that could lower the overall equivalent resistance while keeping the same filtering capacitance.

Keep in mind that I'm not talking Radio Shack stuff. I mean Digikey, Mouser or the like. Coilcraft makes some really nice stuff that you don't see on any motherboard. For example, using a MPP or High Flux core inductor, I would assume that waste heat would drop off because the overall core loss would decrease dramatically. Do you think that an $80 (retail) mobo is using something other than powdered iron core inductors?

Anyway, I was hoping to find out enough parameters on what is there so that I could make simple improvements. If that isn't possible (I doubt that!), I'll have to settle with heatsinks and (possibly) a low noise and low CFM fan on the VRM area.

08-02-2003, 04:03 PM	#12
Brians256 Pro/Staff Join Date: Oct 2001 Location: Klamath Falls, OR Posts: 1,439	Thanks murray13! I appreciate someone answering me with enough knowledge to tell me what I'm up against. I can definitely say that the MOSFETs are a DPAK of some sort. I've been reading up on the datasheet for the Intersil DC-DC converter control chip HIP6302 to learn some of what THEY think is important in selecting components. What I was hoping to find was enough specs on the existing parts to find an alternative with similar but improved parameters. For example, with the improved processes available today, I should be able to get a MOSFET with a similar gate capacitance, switching frequency, and current capability with a lower RDson. Maybe I could even lower both RDSon and gate capacitance. After all, I can buy a couple of $5-10 MOSFET where a mobo manufacturer would want to stick with $1 or even cheaper MOSFETs. I've been reading all the marketing fluff coming out of IRF and similar manufacturers all proud of their trench FETs and so on. So, they must be making things better these days, right? Also, you should be able to do the same thing with the inductors and capacitors. Manufacturers REALLY like to buy cheap stuff. I know that I should be able to buy a pair of low ESR caps that could lower the overall equivalent resistance while keeping the same filtering capacitance. Keep in mind that I'm not talking Radio Shack stuff. I mean Digikey, Mouser or the like. Coilcraft makes some really nice stuff that you don't see on any motherboard. For example, using a MPP or High Flux core inductor, I would assume that waste heat would drop off because the overall core loss would decrease dramatically. Do you think that an $80 (retail) mobo is using something other than powdered iron core inductors? Anyway, I was hoping to find out enough parameters on what is there so that I could make simple improvements. If that isn't possible (I doubt that!), I'll have to settle with heatsinks and (possibly) a low noise and low CFM fan on the VRM area.