matching properties of mos transistors
There is another good paper for mismatch May it helpful for you.
Understanding MOSFET Mismatch
for Analog Design
Abstract�Despite the significance of matched devices in analog
circuit design, mismatch modeling for design application has been
lacking. This paper addresses misconceptions about MOSFET
mismatch for analog design. t mismatch does not follow a simplistic
1 ( area) law, especially for wide/short and narrow/long
devices, which are common geometries in analog circuits. Further,
t and gain factor are not appropriate parameters for modeling
mismatch. A physically based mismatch model can be used to
obtain dramatic improvements in prediction of mismatch. This
model is applied to MOSFET current mirrors to show some
nonobvious effects over bias, geometry, and multiple-unit devices.
Index Terms�Analog circuits, mismatch, semiconductor device
modeling, SPICE.
Added after 11 minutes:
you can search the first paper in this site.
Added after 11 minutes:
Abstract �This paper is concerned with the design of precisionMOS
anafog circuits. Section ff of the paper discusses the characterization and
modeling of mismatch in MOS transistors. A characterization methodology
is presented that accurately predicts the mismatch in drain current
over a wide operating range using a minimumset of measured data. The
physical causes of mismatch are discussed in detail for both p- and
n-channel devices. Statistieal methods are used to develop analytical
models that relate the mismatchto the devicedimensions.It is shownthat
these models are valid for smafl-geometrydevices also. Extensive experimental
data from a 3-pm CMOS process are used to verify these models.
Section 111of the paper demonstrates the applicationof the transistor
matching studies to the design of a high-performance digital-to-analog
converter (DAC).A circuit designmethodologyis presented that highfights
the close interaction between the circuit yield and the matching accuracy
of devices. It has been possibleto achievea circuit yield of greater than 97
percent as a result of the knowledgegenerated regarding the matching
behavior of transistors and due to the systematicdesign approach.