电流镜MOS管的M越大，匹配就越好吗？
时间：10-02
整理：3721RD
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书上说，WL越大，匹配越好，如果WL一定，M越大，整体L的误差就会越小吗?
例如：L=1u W=10u M=2 和L=1u W=5u M=4，哪个匹配度好?
例如：L=1u W=10u M=2 和L=1u W=5u M=4，哪个匹配度好?
WL一定的情况下，over drive电压越大越好
管子个数越多，接触孔就越多，可以减少接触电阻和电容，使匹配更好
二楼正解
例如：L=1u W=10u M=2 和L=1u W=5u M=4，哪个匹配度好?
Both cases have L = 1 um
Area of case 1: 20 um^2
Area of case 2: 20 um^2
Both cases have the same area, and almost identical overdrive voltage (Vgs - Vt), under the same bias current.
I don't think the mismatches make much differences.(From engineering point of view, my answer is no obsevable differences.)