Input stage for a buffer with negative feed-back

摘要

An amplifier stage for a buffer with negative feedback includes an input stage having an input terminal, an output terminal, a first and a second supply terminal, a biasing branch, a first and a second balancing branch each comprising an active transistor for supplying, at the output terminal, a current depending on the current difference in the first and second balancing branches. The biasing branch and the first and second balancing branches are connected in parallel between the first and second supply terminals. The input terminal divides the biasing branch into two input branches having a constant-current generator. Each active transistor is connected to a corresponding current generator for receiving a control voltage correlated with a voltage at the terminals of the current generator.