chapter 6 - Analog IC Design.org

Chapter 6 – Section 3 (5/2/04) Page 6.3-20
5-to-1 Current Mirror with Different Physical Performances
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Poly
Diffusion
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Ground
Output
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Ground
Figure 6.3-6 The layout of a 5-to-1 current mirror. (a) Layout which minimizes
area at the sacrifice of matching. (b) Layout which optimizes matching.
CMOS Analog Circuit Design © P.E. Allen - 2004
Chapter 6 – Section 3 (5/2/04) Page 6.3-21
1-to-1.5 Transistor Matching
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2 1 2 1 2
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Drain 2
Gate 2
Source 2
Drain 1
Gate 1
Source 1
Metal 2 Metal 1 Poly Diffusion Contacts
Figure 6.3-7 The layout of two transistors with a 1.5 to 1 matching using
centroid geometry to improve matching.
CMOS Analog Circuit Design © P.E. Allen - 2004