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发表于 2012-1-22 16:03:27
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发现问题解决问题
1、 Bipolar 和 MOSFET 管的噪声系数分别取决于什么?
Answer:(1)Bipolar transistors, whose base resistance typically dominates the noise figure; MOSfets exhibit only one primary source of noise, that generated in the channel. Thus, in submicron technologies, a reasonable combination of device and bias current may provide acceptably low noise.
(2)Gate resistance of MOS devices also contributes thermal noise, who can be minimized by laying out the transistor as a parallel combination of many narrow device.
取决于不同工艺(GaAs, CMOS |
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