Current feedback composite amplifiers

[velvetsunrise]

Hi,

I have been searching for a good line amp with gain around X10, thats also suitable to drive long cables.

I stumbled upon this current feedback topology from an old Linear Tech application book,

Would this be suitable for a low gain audio line driver?

 

[mickeymoose]

If it is for audio this would be over-kill. How long is your wire? What are the impedances? Balanced or not? E

 

[velvetsunrise]

Hi thanks for your reply, cables are around 10 Meters, poweramp has a 10K input impedance and single ended.
It just seemed with the discreet buffer stage to be an easy to implement and cheep and slightly different approach that may make a nice line amp.

Cheers Steve

 

[AndrewT]

It's a 3transistor DC coupled amplifier with an output buffer.
The extra is a DC servo to minimise the drift in output offset.
If you AC couple this amplifier, you may be able to eliminate the DC servo, leaving a total of 12 transistors for the two channels.