Abstract: A correction circuit (10) includes a transistor (30) that generates a feedback signal for equalizing the amplitude and adjusting the phase of the output signals (V.sub.OUT- and V.sub.OUT+) that are provided at the output of the variable gain amplifier (10). The base terminal of the transistor (30) receives a summed value of the output signals (V.sub.OUT- and V.sub.OUT+). The summed value is inverted and fed back to the differential transistors (12 and 14) and combined with the output signals (V.sub.OUT- and V.sub.OUT+). The output signals (V.sub.OUT- and V.sub.OUT+) have a proper amplitude and phase relationship when the summed value is substantially zero.

Abstract: An RF mixer (10) provides signal gain in a transconductor block (12). A first transistor (36) is sized M times larger than a second transistor (18) to generate the desired signal gain. The gain of the RF mixer (10) is the value M times an output impedance Z.sub.OUT divided by an input impedance Z.sub.IN. A first current (I.sub.40) conducted by the first transistor (36) is matched to a sum of the second current (I.sub.24) conducted by the second transistor (18) and a third current (I.sub.28). The first current is supplied to a first differential transistor pair (46, 48) and the summed current is supplied to a second differential transistor pair (56, 58) to provide balance in switching circuit (50).

Abstract: An RF buffer (10) supplies a single ended output signal and differential output signals. An average voltage of the differential output signals is compared to a reference voltage (VR) by an amplifier (40). The amplifier (40) provides a feedback signal for controlling the bias current conducted by a first transistor (24) and a mirrored bias current conducted by a second transistor (46). The bias currents conducted by the first and second transistors (24, 46) are used to generate the differential output signals (OUT-, OUT+) and are substantially independent of the signal level at an input terminal (20). The signal current conducted by the first transistor (24) controls an output transistor (66), while the signal current conducted by the second transistor (46) controls another output transistor (56) in the push-pull output stage of the RF buffer (10).