Getting 2sk1058/2sj162 and current output

I've looked through some threads here on where to source these transistors but all of the links are old and broken. Also I'm using them to build a 120wpc amplifier into 4 ohms which is about 5 amps rms or 7 amps peak draw. I want it to be able to handle any load and the worst case scenario I've heard of are kappa 9s from infinity that dip below an ohm at a point which would be 28 amps peak draw...is the current rating on transistors a hard limit that if exceeded will blow the transistors right away or will they be able to handle transients that exceed the current limit?
 
You can get them from Taydaelectronics.com as still4given gave me that tip.

I think your application may require an amp design with at least two in parallel to handle that current and that power.

The vHex amp from vzaichenko and Jwilhelm uses 2ea and does 150w I think.

http://www.diyaudio.com/forums/soli...-amplifier-simulated-tina-24.html#post4687317

546633d1462134506-irfp240-9240-amplifier-simulated-tina-2016-05-01-15.17.49.jpg
 

Mooly

Administrator
Paid Member
2007-09-15 8:14 am
Semiconductor current ratings are normally assumed to be an absolute, an absolute that has to be considered along with the safe operating area or SOAR of the device, and it would be a poor design and designer that purposely designed on the 'it will probably be OK basis'.

The big problem (and advantage in some ways) of lateral FET's is that they tend toward 'self limiting' when pushed very hard, in part because of the fall in 'gain' or more correctly fall in transconductance. They are tough though. That said, 120 watts RMS into 1ohm is probably unrealistic as a design target for a lateral FET amp that also has to be similarly specified into 4 ohms. The supply voltage needed would mean several pairs of devices are needed.

The old Hitachi/Renasas devices are long obsolete but you might want to check out the latest lateral devices from SEMELAB which are available from the usual suppliers. You can get double die FET's which are like two in parallel in one package, so 14A rated rather than 7.

TT Electronics | Products

There is also a very good application note (attached).
 

Attachments

  • Alfet Application Note.pdf
    831.9 KB · Views: 62
The old Hitachi/Renasas devices are long obsolete but you might want to check out the latest lateral devices from SEMELAB which are available from the usual suppliers. You can get double die FET's which are like two in parallel in one package, so 14A rated rather than 7.

Renesis is still producing those devices. They can be special ordered through Digikey for a premium.