Allen and Holberg - CMOS Analog Circuit Design

V.6 - SUMMARY

•The circuits in this chapter represent the first level of building blocks in analog circuit design.

•The MOS transistor makes a good switch and a variable resistor with reasonable ranges of linearity in certain applications.

•Primary switch imperfection is clock feedthrough. In order for switches to be used with lower power supplies, VT must be decreased.

•The primary characteristics defining a current sink or source are VMIN and Rout. VMIN → 0 and Rout → ∞. Typically the product of VMIN times Rout is a constant in most designs.

•Current mirrors are characterized by:

Gain accuracy

Gain linearity

VMIN on output

Rout

Rin

•Reasonably good power supply independent and temperature independent voltage and current references are possible. These references do not satisfy very stable reference requirements.

VI. CMOS AMPLIFIERS

Contents

VI.1 Simple Inverting Amplifier

VI.2 Differential Amplifiers

VI.3 Cascode Amplifier

VI.4 Output Amplifiers

VI.5 Summary

Organization

Chapter 10

Chapter 11

D/A and A/D

Analog Systems

VI.1 SIMPLE INVERTING AMPLIFIERS

CHARACTERIZATION OF AMPLIFIERS

We shall characterize the amplifiers of this Chapter by the following aspects:

•Large Signal Voltage Transfer Characteristics

•Maximum Signal Swing Limits

•Small Signal Midband Performance

Gain

Input resistance

Output resistance

•Small Signal Frequency Response

•Other Considerations

Noise

Power

Etc.

Allen and Holberg - CMOS Analog Circuit Design Page VI.1-4

Allen and Holberg - CMOS Analog Circuit Design Page VI.1-8

High Gain CMOS Inverters

Large signal transfer characteristics of inverter with a current source and push pull inverter