Well I was thinking of two possibilities for active attenuators.
Firstly using a negative feedback amp with suitable arrangement of feedback.
There are practical limits to this, but it can be done.
Since the amp must be inverting it needs a common emitter stage. The gain of a common emitter stage is approximately beta times the load reisitance divided by the source resistance. So we make the source resistance high by adding a series resistor.
The second way is to use an emitter/cathode/source follower (common collector) and split the emitter resistor, tapping off the attenuated voltage as shown.
Of course there is a whole variety of passive attenuator networks such as T, H or pi networks, that are available, but I am not sure if these are acceptable.
In these terms your reisitive divider is called an L pad network.
Firstly using a negative feedback amp with suitable arrangement of feedback.
There are practical limits to this, but it can be done.
Since the amp must be inverting it needs a common emitter stage. The gain of a common emitter stage is approximately beta times the load reisitance divided by the source resistance. So we make the source resistance high by adding a series resistor.
The second way is to use an emitter/cathode/source follower (common collector) and split the emitter resistor, tapping off the attenuated voltage as shown.
Of course there is a whole variety of passive attenuator networks such as T, H or pi networks, that are available, but I am not sure if these are acceptable.
In these terms your reisitive divider is called an L pad network.
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