Agilent Technologies 93000 SOC Series Training Manual page 356

Lesson 5 – Executing the ADC Distortion Test
Even an ideal ADC produces a quantization error which can be
seen as a sawtooth function.
Ideal ADC
Binary Output Code
111
110
101
100
011
010
001
000
1/8
Quantization Error
+1/2 LSB
–1/2 LSB
ADC Quantization Error
But other factors also reduce the available resolution:
Calculation of N
EFF
356
1/4 3/8 1/2 5/8 3/4 7/8
Analog Input
FS
Analog Input