AT-HA-5000 schematic

[EUVL]

If you have followed our UTHAiM project, you would be aware of our positive experience of using lateral power MOSFETs as output devices.
UTHAiM -- Just for Fun
Apart from many advantages sich as negative tempco and hence simple biasing, it has real drive power and bass control.

You could actually turn the AT into a much simpler circuit but with similar distortion signature by using the UTHAiM output stage here instead.
The attached spice file is simulation only and have not been test built.
But it gives you a good idea how it may look like, without the need to use UHC-MOSFETs.
The distortion spectrum is essentially the same as that of post #99, rather surprisingly.


Patrick
.

 

[EUVL]

2SK2955 / 2SJ554 Curve Tracing

I finally found some time to measure my 20 pairs of 2SK2955 / 2SJ554 bought from Japan some 10 years ago.
As you can see they are not truely complementary.
The NMOS (in red) has higher Vgs but somewhat lower Yfs (at 1.2A).
But they more or less compensate with each other if you make allowance for that in circuit design.
Extremely thermal sensitive, just like 2SK3497 / 2SJ618 so some bias control is a must.
Transconductance at 1.2A is > 10S, almost double that of the Semisouths.

If you can tame them thermally, they will drive anything.


Patrick

.

 

[blackdod]

If you have followed our UTHAiM project, you would be aware of our positive experience of using lateral power MOSFETs as output devices.
UTHAiM -- Just for Fun
Apart from many advantages sich as negative tempco and hence simple biasing, it has real drive power and bass control.

You could actually turn the AT into a much simpler circuit but with similar distortion signature by using the UTHAiM output stage here instead.
The attached spice file is simulation only and have not been test built.
But it gives you a good idea how it may look like, without the need to use UHC-MOSFETs.
The distortion spectrum is essentially the same as that of post #99, rather surprisingly.


Patrick
.

I bought some 1056/162 (I wait that be originals) I´ll try to do this amp although the pcb I think it will be quite large and expensive.

 

[EUVL]

It is not more complex than the UTHAiM, which is 45x50mm per channel.
Almost all through hole.


Patrick

 

[Ropha3r]

Chinese ha5000 schematics.

 

[Ropha3r]

Schematic and pcb of polish clone of the ha5000.

Adjustment guide oversized due to the local file limits:
Machine translated: Opis montażu, uruhomienia i regulacji wzmacniacza HA2012.pl.en.pdf | DocDroid
Polish original: Opis montażu, uruhomienia i regulacji wzmacniacza HA2012.pdf | DocDroid

 

[Ropha3r]

I've found on my desktop some old photos of unpopulated chinese ha5000 clone boards. (Half-populated now, waiting in the cardboard anyway)

Maybe it can be helpful for someone.

 

[ripson]

As you can see they are not truely complementary.
The NMOS (in red) has higher Vgs but somewhat lower Yfs (at 1.2A).

A few years ago I bought 60-80pcs of used (desoldered) 2SJ554 and 2SK2955 from China, I can't be 100% sure that they are genuine Renesas / Hitachi, but usually fakes aren't sold used...

From this batch I chose these pairs, the N-channel has jigher gain and tendency to higher Vgs, both have 3150 pF input capacitance.

 

[ripson]

off-topic but comparison with other MOSFETs attached: 2SK1530, FQA19N20C and IRFP240