| 摘要 |
<p>A wide dynamic range transconductance stage has two branches, each branch being composed of a plurality of transconductance circuit paths. Each circuit path has a greater transconductance than the other circuit paths for its branch within a respective sub-range of the input signal range for the stage as a whole, with each path dominating the other paths for its branch within its respective sub-range. The overall bandwidth for the stage, its gm, its noise characteristics and its input voltage range are enhanced as a result. Bandwidth and slew rate may be independently optimized by the designer. Two paths are used for each branch in the preferred embodiment, with one path consisting of a bipolar transistor (Q3,Q4) and the other path either a field effect transistor (J3,J4) or a resistor degenerated bipolar transistor (Q5,R5;Q6,R6). Multiple paths may be used based on the same principle. <IMAGE></p> |
