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What is the need of current mirror?
The current mirror is used to provide bias currents and active loads to circuits. It can also be used to model a more realistic current source (since ideal current sources don’t exist).
How do you construct a current mirror using a BJT and Mosfet?
The first trick to use bipolar junction transistor as a current mirror circuit is to construct an exponential voltage to current converter using the transistor. This is done by providing a voltage across the base-emitter junction of the BJT and the collector current is taken as an output.
Can a mirror circuit be implemented using two MOSFET transistors?
Current mirror circuit can be easily implemented using two MOSFET transistors. The working of the MOSFET current mirror circuit is similar as described in the previous transistor section. Consider the above current mirror circuit using MOSFET, the MOSFET transistor M1 is in the saturation region as the V DS ≤ V GS.
Is the current mirror circuit using BJTs equal?
The current mirror circuit using BJTs is shown below. Assume that these transistors are equal so both the transistors operating temperatures as well as device parameters are similar.
Which is the ideal configuration for a mirror circuit?
A current mirror circuit, mirror or copy the input current of one active device to the other active devices output. An ideal current mirror circuit is an ideal current amplifier with the inverting configuration that can reverse the current direction. Therefore, for an ideal current amplifier, the current transfer ratio is an important parameter.
Which is the saturation region of the MOSFET transistor?
The working of the MOSFET current mirror circuit is similar as described in the previous transistor section. Consider the above current mirror circuit using MOSFET, the MOSFET transistor M1 is in the saturation region as the V DS ≤ V GS.