I am designing a PTAT (proportional-to-absolute-temperature) current generator with 2 PMOS transistors for a bandgap circuit.
In which way does the aspect ratio of a MOS transistor (M1 and M2) influences the current mismatch?
why is important that W/L is <1? Is it a rule of tumb for the aspect ratio? (I am using W=1u and L=6u)