| 摘要 |
An active bias circuit 30 connected to a power amplifier PA maintains a power amplifier DC quiescent current at a fixed value over a wide temperature range. The active bias circuit 30 includes first and second current mirror circuits 32, 34. The power amplifier PA is an element of the second current mirror circuit 34. A temperature compensation circuit 42 is connected to the first current mirror circuit 32 for providing temperature compensation therewith. A first reference voltage source is connected to the first current mirror circuit 32 by way of the temperature compensation circuit 42 for providing a first reference voltage Vref to the first current mirror circuit 32. A current sink 36 is connected to a transistor of the first current mirror circuit 32 and a voltage source adjustment circuit 38 is connected to the first current mirror circuit 32 for setting a voltage provided to the first current mirror circuit 32. |
