diarmuid
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Hello,
Maybe someone can solve my confusion regarding the above question.
My confusion stems from the following:
1.) From a design perspective I would say, larger Vt gives lower Vov and so, for a given Vgs and Vds, would push
the device further into saturation, yielding a higher output impedance and hence more ideal current source.
From that I would say higher VT is better for matching.
But...
2.) Today I heard lower VT is better for matching. Why is this? Is it because higher VT devices have doping
implants which are difficult to match?
So going from 1 and 2 above, say I want to design a simple current mirror. Do I go for high or low VT?
Any help greatly appreciated to alleviate my stumbling confusion!!!
All the best,
Diarmuid
Maybe someone can solve my confusion regarding the above question.
My confusion stems from the following:
1.) From a design perspective I would say, larger Vt gives lower Vov and so, for a given Vgs and Vds, would push
the device further into saturation, yielding a higher output impedance and hence more ideal current source.
From that I would say higher VT is better for matching.
But...
2.) Today I heard lower VT is better for matching. Why is this? Is it because higher VT devices have doping
implants which are difficult to match?
So going from 1 and 2 above, say I want to design a simple current mirror. Do I go for high or low VT?
Any help greatly appreciated to alleviate my stumbling confusion!!!
All the best,
Diarmuid