i am confuse with the layout of multiple MOS. for example, i have a MOS with a size of 10 and assume i divided them evenly into 4 MOS with the size 2.5 each. may i know the correct way to connect the gates and drain/source?
should they connect in series or parallel as shown in the attachment and the reason why. please advise.
may i know the correct way to connect the gates and drain/source?
should they connect in series or parallel as shown in the attachment and the reason why.
Always in parallel, always to one side (doesn't matter which one).
Why? Minimize parasitic capacitance!
S. the example from the CMOS Transistor Layout KungFu book below.
In erikl's attachment, the second illustration is better than the third because the gates are not connected with poly. This reduces antenna effect during poly layer etching.
Obviously in parallel, drain and source are interchangable.
it seems you are new to IC layout, Not to worry i would suggest you to first go through the basic IC layout books or tutorial and start doing it.........
Of couse you should connect S/D in parallel, respectively.
And connect gate all together.
You'd better to connect gate by metal rather than poly, and put more contacts (two is ok for most layout) if it will not hurt your area.