Current Mirror Mosfet Formula. 2 ikv v d gs t say we want this current d. The simple two transistor implementation of the current mirror is based on the fundamental relationship that two equal size transistors at the same temperature with the same v gs for a mos or v be for a bjt have the same drain or collector current.
We will parameter value v t 2 1 v nc ox w l 180 ma v2 v a 50 v. The compliance voltage where the v dg 0 and the current mirror behavior still works in the lowest output voltage can be calculated like this. 2 measurements the parts that will be used to build the current mirror circuit are listed in table 2 and can be obtained from the ee stores along with bread boards and wiring equipment.
Ds gs v v and thus.
Referring to figure 8 one can see that i ref i c 2i c i c 1 2 2 4 for a pair of matched transisfor i o i c and the current transfer ratio becomes i o i ref i c i ref 1 1 2 2 5. O for the current mirror when it is biased under these conditions. What is the small signal voltage gain v o v i. The implementation of the current mirror circuit may seem simple but there is a lot going on.
