Patent attributes
An attenuator circuit (10) having two or more branch circuits (12a to 12e) has inputs (14a to 14e) for the branch circuits (12a to 12e) being connected essentially in parallel arrangement to an input port (20) for the attenuator circuit (10). Each branch circuit (12a to 12e) includes one or more bipolar transistors (32a to 32e) having a collector element receiving a signal from a power supply (24) through at least one RF positive-intrinsic-negative (PIN) diode (50a-50d) that a control circuit (24) is controlling. At least one resistive element (16a) couples an input (14b) of a second (12b) of the plurality of branch circuits (12a to 12e) from the input port (20) to the branch circuits (12a to 12e). Thus, each branch (12a to 12e) of the attenuator circuit (10) draws current from a low voltage power supply (24) while still providing for sequential biasing of successive branches and linearization of overall control characteristics.
