tda8768a NXP Semiconductors, tda8768a Datasheet - Page 26

• Manufacturer Part Number: tda8768a
• Description: 12-bit, 70 Msps Analog-to-digital Converter Adc
• Manufacturer: NXP Semiconductors

Philips Semiconductors
9397 750 09656
Product data
12.1.4 Noise Power Ratio (NPR)
The total intermodulation distortion IMD is given by
where,
and
is the power in the intermodulation component at frequency f
When using a notch-filtered broadband white-noise generator as the input to the ADC
under test, the Noise Power Ratio is defined as the ratio of the average out-of-notch
to the in-notch power spectral density magnitudes for the FFT spectrum of the ADC
output sample set.
IMD dB
P
a
P
+
intermod
signal
2
im
a
2
im
f
t
f
=
t1
=
=
+
a
2
a
2 f
10
2
im
f
log
t2
t1
f
+
t1
+
Rev. 02 — 03 July 2002
P
-----------------------
a
a
–
P
intermod
2
2
im
signal
f
t2
f
2 f
t2
–
t1
a
–
2
im
12-bit, 70 Msps Analog-to-Digital Converter (ADC)
f
t2
f
t1
+
+
a
f
2
im
t2
2 f
+
a
t1
2
im
+
f
f
t2
t1
–
© Koninklijke Philips Electronics N.V. 2002. All rights reserved.
2 f
t2
t
.
TDA8768A
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