2sa1302/2sc5200 Power Expected?

[zox2003]

How much power I can expect from pair of this transistors on +/- 40V rails.

Amplifier construction:

TL081---tip29/30 (drivers)---2SA1302/2SC5200 ( OUTPUT)


Thanks.

 

[edl]

+/-40V rails means an 56V-CT trafo.

then you will get 100W sinus on 4ohm or 60W sinus on 8ohm.

 

[zox2003]

Power on 4 ohms

Transformer is 2 x 30 V .Can I use pair of this on 4 ohms with this voltage ( approx. 2 X 41V DC).

Thanks

 

[edl]

hello

then with this trafo you'll get 110W sinus-power on 4ohm.
a pair of output devices would do the job, but because of the safe let's use 2 pairs of them by channel!

regards

 

[Zero Cool]

I have some amp modules that use 4 pairs and +/- 75VDC and the produce 220+ @ 8 and 350 or better @ 4 ohms.


Zc

 

[anatech]

Hi zox2003,
Just curious. Are you using a normal emitter follower configuration? If so, your output swing is limited by the op amp power supply less a few volts. Mr TL081 will not survive much over bipolar 15VDC supplies so ...
-Chris

 

[jacco vermeulen]

Meaning you will need an extra gain stage between the opamp and the driver to have enough voltage gain to reach the 30vdc on the output.

 

[K-amps]

Looking at the data sheets, the pair will not pass more than 0.4 amps at that rail voltages.... experience tells me 75 watts to 120 watts is possible with one pair if you push it.

 

[sajti]

If You design Your amplifier for maximum output (ie.. low rail losses), and the transformer can handle about 400-500VA, 75W/8ohms, and 120-130W 4ohms is possible. But I recommend to use two pairs for 4ohms!

sajti

 

[zox2003]

Power from Amplifier

I guess that with TL081 and emiter follower design I can reach 200W on 4 ohm with no problem ( 4 transistors-2 per rail).
Right?

 

[K-amps]

Re: Power from Amplifier

I guess that with TL081 and emiter follower design I can reach 200W on 4 ohm with no problem ( 4 transistors-2 per rail).
Right?

Bridge and get 300 -400 watts 8 ohms. ;-)

 

[anatech]

zox2003,
Do you have another stage to provide additional voltage drive to the output stage?? If you don't the max you will get is 25W into a 4 ohm load, 100W bridged in an optimistic, perfect world.

That's assuming you are running the op amp off a +-15VDC supply. If you don't provide +- 15VDC and connect it to the rails the chip will explode. We're talking a big, loud snap with maybe a sizzle. Could be fun you know. I think jacco wants to watch as well.

-Chris

 

[zox2003]

????

How did you get just 25W.
If I am right I can run this amp easy to 150W with op amp without additional drive.

op amp----2x drivers (emitter folowers)---output transistors

TL081------TIP29/30-----2SC/2SA


Tell me if I am wrong...

 

[zox2003]

schematic is here

HEre is a schematic.How much power I can expect in this configuration?

 

[Greg Erskine]

Amplifier construction:
TL081---tip29/30 (drivers)---2SA1302/2SC5200 ( OUTPUT)

Hi zox2003,

I think the 2SA1302 is a superseded transistor. The compementary to the 2SC5200 is the 2SA1943.

 

[anatech]

Hi zox2003,
So how much voltage swing will you have to the drivers? Hint: If you increase the supplies to +- 300VDC it won't change.

There is no more voltage gain between the op amp and the drivers. You are therefore restricted to the available output voltage from the op amp. Your extra supply voltage only generates heat in the output stage, nothing else.

-Chris

 

[jan.didden]

Chris,

There IS voltage gain from the output to the drivers. But without the resistor values, it is impossible to say how much.

Jan Didden

 

[jacco vermeulen]

Ok, here it is : You are wrong !

 

[darkfenriz]

zox2003

Your topology is O.K. and you could get close to P=Vrail^2/2*Rload
but in fact there is no (discrete) emitter follower stage in it.
That's the cause of these misunderstandings
regards

 

[jan.didden]

Ok, here it is : You are wrong !

Who?