Controllable operational transconductance power amplifier (controllable
power OTA) including an input stage receiving a differential input signal
(Ovin) and deriving therefrom first (i1) and second (i2) low power
current signals being coupled to first (ccs1) and second (ccs2) current
controlled output current sources being arranged in class B push pull
configuration. To obtain an effective gain control while securing power
efficiency and linearity, the overall gain of the power OTA is controlled
by varying the gain or transconductance of the input stage (c15) and by
the use of means for bi-directionally rectifying said first (i1) and
second (io) low power current signals and providing in mutual alternation
power amplification of said first (i1) and second (i2) low power current
signals into first (I01) and second (Io2) mutually exclusive high power
current output signals, which are supplied through a current summer to a
current output (I0) of said linear power amplifier.