CPC1465
Figure 4. Test Circuit for ac Impedance and Linearity
68 μF
DUT
Vmt
ISL
1 - 20 mA
dc current source
VAPP
ac generator
1k Ω
Vsig
1000 × Vmt
Zmt = ---------------------------
Vsig
Vmt
Linearity = 20log --------------------------------------- + 20log -----------
Vsig2ndHarmonic 67.5
1000
Figure 5. Linearity Requirement Template
Acceptable
75
Unacceptable
50
0
0
0.5
10.0
10.5
11.0
11.5
12.0
Applied ac Voltage (VPP)
6
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R02