Lateral MOSFET replacements for 2SK1058 (Hitachi)

[jgwinner]

Folks:

I'm having problems sourcing the Hitachi 2SK1058 (or BUZ900P) L-MOSFET. I've checked the forum threads, and found a few leads, but they are all fairly expensive.

Is their an IR substitute for this part? Reference my other thread (high voltage ESL SS amp), are their any parts that would go over 200v and still have good audio characteristics?

I can get the 2SK1058 from Randy Sloan, but as I'm buying a 'hobbyists' large number of them (24), I was hoping to find a cheaper source. His prices aren't bad, but at close to $200 of transistors I want to see if there are alternates.

I tried Mouser, Digi-Key, Allied, and a few others, to no avail. I found a few DIY audio parts places that had them for slightly more than Randy Sloan himself (2SK1058/2SJ162 L-MOSFET pairs...$16.00 per pair). I checked all the threads that ref'd this part but didn't find anything cheaper than Sloan.

I've found Singapore distributors that have them for $2.10, if I buy 2,378

[peranders]

Check http://www.elfa.se/elfa/produkter/se/20/2022236.htm (frame page)

They sell them for approx. 10 USD a piece.

They have pages in english but there's no search yet. Try the swedish section (blue and yellow flag) and look for SÖK (=search). It's located at the top of the left frame.

To answer your question: These FET's are special in many ways and can't be replaced easily. You must have deep knowledge about the design they are in, otherwise it can be hard (impossible?) to get it working with other FET's.

[seangoesbonk]

Originally posted by jgwinner
Randy Sloan himself (2SK1058/2SJ162 L-MOSFET pairs...$16.00 per pair).

I have also been looking EVERYWHERE for these. I have pretty much decided to get them from Mr. Sloan. The cheapest I found was about $6.50usd each, but not matched. Because these are not cheap, I can't just buy 100 pairs and match them myself. So I'll spend the extra $1.50usd each to have them matched for me.

Well, good luck and let the rest of us know if you find a better deal.

[jgwinner]

Originally posted by seangoesbonk

The cheapest I found was about $6.50usd each, but not matched.

Randy himself said they don't need to be matched:

The L-MOSFETs incorporated in the OPTI-MOS amps do not require any "matching" techniques (don't confuse L-MOSFETs with the D-MOS families used in many automobile hi-fi systems).

Still, that's only a three buck difference, so you may still have a good point, although with 24 output devices that adds up.

[mlloyd1]

For the quantity you're talking about, did you try Hitachi directly or a regional distributor? That's how I bought all the Hitach power MOSFETs I've ever had. Great price (relative to, say, MCM), and I always got related lot groups, so I didn't really have to match them.

Maybe you can engineer a group purchase to drive the cost down further?
mlloyd1

[QUOTE]Originally posted by jgwinner
[B]Folks:

I'm having problems sourcing the Hitachi 2SK1058 (or BUZ900P) L-MOSFET. I've checked the forum threads, and found a few leads, but they are all fairly expensive.QUOTE]

[jgwinner]

I don't mind making a group purchase.

Does anyone else want some? Let me know what Qty you are interested in. Sloan's design has 4 devices (2 complimentary pair).

[Silverpike]

An excellent replacement for these parts can be found at Profusion PLC . They carry the Exicon lateral MOSFETs (mentioned in Randy's book). You can get them for less than $5 a piece now (wow!).

If you look at the datasheets, these parts are slightly better than the Hitachis. It has been awhile since I last looked at them, because I am no longer going with one of Randy's design for my amp.

[jgwinner]

Silverpike:

That was an excellent source!

The ECX10N20 seems to be a slightly higher voltage version, as near as I can tell identical (the ECX10N16 is the cross, but I'm looking for higher voltage anyway).

2SK1058      ECX10N20 

Vdsx                   200        160
Gate-Source             14        15
Current                 8A         7A
Power                 125w       100w
Gate-Srce Bkdn        +-14       +-15
Input capacitance    500pf      600pf
Output capacitance   300pf      350pf
Turn On time         100ns      180ns
Turn Off time         50ns       60ns

So as near as I can tell they are faster and slightly better, and are cheaper. I'm not sure I'm qualified to read the output traces though. Do you think this would be an adequate subtition part?

[FEThead]

I bought mine from Avnetmarshal ( www.avnetmarshal.com ) As of June 18 they show a price of $4 USD with a minimum buy of 30. They also say they are out of stock. If you guys do a group buy this source might work. Good Luck.

[Silverpike]

Yes jgwinner, the Exicon ecx10n** parts are drop in replacements for the P and N channel Hitachis you identify. There is even a table on the Profusion web site stating this also. They should work fine.

As an added bonus, I am under the impression that they sound better than the Hitachis. I have not heard them myself, but I have seen comments on the net elsewhere to this end.