Bridging many op amps

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No , i don't need to paralell them. I need an output voltage of around 200V Rms and very low current. I need it to drive audio signal - now i am thinking about 3584JM chip - is it suitable for audio frequencies ?
I was unable to find it's distortion curves.

Thanks ,
Lukas
 
Operation

The maximum power of the amplifier is primarily set by the supply voltage (18V). The maximum output voltage is approximately 16V. With 8 ohm speakers, the power rating is 16 Watts per channel. With 4 ohm speakers, the power rating doubles (32W per channel). Continuous power output equals the peak power output since, except for the supply voltage, power supply is "over-dimensioned".

Each LM6171 opamp is able to deliver up to 150 mA of current, we have 6.6 Amps per channel.

With 16V output, the amp should drive loudspeakers down to 2.5 ohm. In this case, the output impedance effectively seen by each separate opamp is 44 x 2.5 + 10 = 120 ohms and does not represent a major problem (LM6171 is specified for impedances down to 50 ohms).

This amplifier uses 44 op-amps LM6171 in parallel
:)

An externally hosted image should be here but it was not working when we last tested it.


more info A Precision Preamplifier-Power Amplifier System
 
Bazukaz said:
I don't want to use output trannie generally,
so an Op-amp with high voltage transistor would be OK.
It could operate in class A mode, but where to find a schematic ?

Maybe an OP-amp with high volt transistor output stage.

You need a transformer with at least secondary 2x200 Volt, anyway.
And another trafo for OP-amp supply.


I can say for sure, you will not find any such schematic.
But if you tell exactly what you are trying to do,
maybe someone here could try to design a circuit for you.

I guess a few here know about high voltage circuits, for television.
A good Output Transformer to raise the voltage might be the best idea ....
 
Bazukaz said:
Hi,
Is it possible to bridge more than 2 op amps , lets say , 8 ?
I need higher voltage and low current at output. I would use LM833 or similar op amps.

Yes, you can bridge more than 2, but you will need floating power supplies. For 4 op-amps bridged you will need two 'grounded' and two floating supplies. I don't think it is very good idea though.

regards
 
Hi,
Thanks a lot,
I am thinking about driving electro-static headphones directly with a transistor amp.I have found one circuit diagram for it .

Few questions :
Could take out first two op amps ? And substitute BUK456 with something else , like IRFBG30 ? What changes to other components may be required ?

Regards ,
Lukas
 

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