TDA8768A Datasheet, PDF (25/32 Pages) NXP Semiconductors – 12-bit, 70 Msps Analog-to-Digital Converter (ADC)

Philips Semiconductors
TDA8768A
12-bit, 70 Msps Analog-to-Digital Converter (ADC)
Signal-to-Noise Ratio (SNR): The ratio of the output signal power to the noise
power, excluding the harmonics and the DC component.
SNR[dB] = 10log ^P-_P---^s-_n--ⁱ-_og---_in--_s-^a-_e-^l
Spurious Free Dynamic Range (SFDR): The number SFDR specifies available
signal range as the spectral distance between the amplitude of the fundamental and
the amplitude of the largest spurious (harmonic and non-harmonic, excluding DC
component.
SFDR[dB] = 20log _m-----_a--^a--_x-¹--₍--_s---₎
12.1.3 Intermodulation distortion
Spectral analysis (dual-tone)
005aaa023
0
-20
(dB)
-40
IMD3
-60
-80
-100
-120
-140
-160
0
2.5
5
7.5
10
12.5
15
17.5
20
22.5
25
27.5
measured output range (MHz)
Fig 27. Spectral analysis (dual-tone)
From a dual-tone input sinusoid (f_t1 and f_t2, these frequencies being chosen
according to the coherence criterion), the intermodulation distortion products IMD2
and IMD3 (respectively, 2nd and 3rd-order components) are defined, as follows.
IMD2 (IMD3): The ratio of the RMS value of either tone to the RMS value of the worst
second (third) order intermodulation product.
9397 750 09656
Product data
Rev. 02 — 03 July 2002
© Koninklijke Philips Electronics N.V. 2002. All rights reserved.
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