Current Sources and Voltage References

Characteristics of CMOS FETs

Using Analog CMOS Arrays to Create Current Sources

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9.2 Characteristics of CMOS FETs

CMOS FETs share most of the same characteristics of the low-power enhancement-

mode devices DMOS FETs that are described in Chapter 8. However, CMOS designs

combine both N-channel and P-channel transistors on the same substrate, whether

digital gates or analog op amps. Typically, the N-channel MOS device is used as the

driver, while the P-channel transistor is used as its active load. The sensitive inputs

and outputs of most CMOS devices employ protective diodes to guard against dan-

gerous static ESD voltage transients. Without this ...