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Note: (W/L)ratio of M5 = 3 * (W/L)ratio of M7

I would like to ask if there is a preferable method for accurate current mirroring between the two schematics below. To make it clear what I would like to say, in the left schematic we have a simple current mirror and we want to provide in the load three times the current of M7 (so the purpose is the Iload = 3mA).To achieve this I will choose the W/L ratio of M5 to be three times greater than the W/L ratio of M7.

On the other hand to achieve the same purpose in the right schematic we place four identical transistors (M1,M2,M3,M4) with the same W/L ratio. So I know that the load will have again three times bigger current (3mA).Which schematic provide better accurate current mirroring?

Advantages, Disadvantages for these typologies?

I have read that the right schematic gives us better accuracy. Is it true?

enter image description here

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Currents are only accurately mirrored IF the transistors are identically constructed (implants, gate sizes, contacts, metals, etc including the surrounding implants affecting outgrowth of the mirroring-devices implants and surrounding metal/poly that affect the electric fields), and the temperatures are identical and the I_V operating conditions are identical.

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