Patent ID: 6313667
Filing Date: 2001-11-06
Classification: H03F,H03K

Abstract:
An apparatus for a circuit with an input voltage range that is independent of the output voltage range, comprising:(a) an input stage adapted for receiving an input signal, a current provided by a first current source flows substantially through one of a first switch and a second switch when one of the first and second switches is activated by an unequal polarity of the input signal and another of the first and second switches is deactivated by the unequal polarity of the input signal;(b) a turn around stage that outputs an output signal when the polarity of the input signal is unequal, the flow of the current through the one of the first and second switches that is activated causes one of a third switch and a fourth switch to be deactivated and the other one of the third and fourth switches to be activated and conduct an output current that is substantially larger than another current that flows through the one of the third and fourth switches that is deactivated; and(c) a bias circuit for separately providing a floating bias for the operation of the third and fourth switches, a fifth switch biases the operation of the third switch and an emitter of the fifth switch is cross coupled to an emitter of the fourth switch, a sixth switch biases the operation of the fourth switch and an emitter of the sixth switch is cross coupled to an emitter of the third switch, wherein the cross coupling of the emitters of the fifth and sixth switches reduces noise and power consumption of the circuit.