rules for mos transistor matching

·minimal matching:

typical three-sigma drain current mismatches of several percent. minimal matching is often used for constructing bias current networks that do not require any particular degree of precision . this level of matching corresponds to typical in excess of ±10m v and is therefore inadequate for voltage matching applications.

·moderate matching :

typical three-sigma offset voltage of ±5m v or drain current mismatches of less than ±1%. useful for constructing input stages of non-critical op-amps and comparators ,where untrimmed offsets of ±10m v can be maintained.

·precise matching:

typical three-sigma offset voltages of less than