stk4241v

[morpheus82]

hi guys,
I hope somebody has some experience with this component...I'd like to build an amplifier with the stk4241, but I have a +/-30V power supply and a 4ohms load...Is it possible?does it work?an how much power can it deliver?
thanx a lot...
max

[Netlist]

I'm afraid its made for higher supply voltage and 8 ohm load.

Can we help you with the datasheet ?

Homepage: http://katalog.elektroda.net/

/Hugo

[Morbid]

i've built stk 4046XI on 27VOLT dual supply and it worked well...
see my other thread of resistor burn at 4ohm load

[Stuart Easson]

Approximate power from a +-30v supply into resistive 4 ohms is easy...

Assuming 3 volts dropped in the PSU, across the output devices, emitter resistors etc the peak voltage swing is +-27, since power = v^2/resistance, peak power is approx. 180w, rms power is half peak power, ie 90w.

If you plan to really use this power, say for a gig, party, etc you will need a PSU capable of 5 amps per channel average for that output level, or the voltage will 'droop' further and less output will be available...thats 300va per channel...not a trivial amount...

Stuart

[Stuart Easson]

The datasheet shows output power with rails down to +-25 volts, so you are getting close to the lower end of the scale, going too low will eventually screw up the bias and increase distortion etc...

At a minimum, (based on 120wRMS/8ohms) the device has a current capability of approx. +-5.5 amps, so at your supply voltage you shouldn't run into issues, but again you are close to the limit, probably shouldn't push your luck too far, ie +-35v rails with 4 ohm load might kill the thing...

Good luck

Stuart

[morpheus82]

morbid, u say that it works with +-27V...but with a 4ohms load or a 8ohms load?so, if it's with 4, it must work with30...I know that the datasheet doesn't say anything about the 4 ohms, but I think it won't be a problem(I hope..)
Better Ideas for an amplifier 100wrms with a single layer pcb?
thanx...

[morpheus82]

and what about a pari of stk4044v?+-30V are ok for this, always at 4 ohms?
(If somebody has something better than the sanyo datasheet, I'll be very pleased to know where to find it!!)

[Stuart Easson]

I'd recommend checking out the 4040 series, I know of 2 examples yielding 100w/4 per module...I recently dismantled an old pyramid car amp, rated at 2x100w into 4 ohms per channel. Before cannabalizing it I checked it's max output and it *just* met it's specs with a hard 14.5v into the SMPS. The modules it used were 4040xi (fully complementary) with approx. +-36v rails. For years Velodyne used the 4040iv (quasi complementary) in their servo subs, and rated the output >100w, though I havent verified this number yet...

I have recently purchased more of the 4040xi, not sure if the other version is still available.

Good luck

Stuart

[filgor]

hi morpheus82,

To answer your email to me earlier..

From what I know both the 4241 and 4048XI should work OK with +/- 30 volts. In both cases the distortion may be slightly higher than if you used a higher voltage.

At +-30 volts heat dissipation and output current won't be a massive issue so besides a few extra watts you won't get much more out of a beefier single channel like an stk4048.

The 4241 has 2 channels capable of ~72 watts each into 4 ohm loads with +-30 Volts if regulated. The 4048xi has 1 channel capable of ~77W at the same voltage. This less than expected performance is due to STK's having ghastly clipping voltages at the high current outputs required of 4 ohm loads.

Remember also that these figures would be worse if the Power supply is not a feedback regulated Switched Mode Power Supply and far worse if you're not using a SMPS at all!

PS. STK's seem to have a reputation for being hazardous when it comes to oscillations so watch your gain, layout and grounding.

[morpheus82]

hey, I have 2 toroids rated 800VA double output 25V...secondary rated for 32A...custom made...It's a great unregulated power supply!!with 33000uF at the out...Why it won't work fine?