TDA6650ATT Datasheet, PDF (39/54 Pages) NXP Semiconductors – 5 V mixer/oscillator and low noise PLL synthesizer for hybrid terrestrial tuner (digital and analog)

NXP Semiconductors
TDA6650ATT; TDA6651ATT
5 V mixer/oscillator and low noise PLL synthesizer
AM = 30 %
50 Ω 1 kHz
unwanted
e_u
signal
source
AC
HYBRID
50 Ω
B
wanted
e_w
signal
source
D
50 Ω
AC
HYBRID
BD
50 Ω
HBIN1 IFOUTA
DUT
C
HBIN2 IFOUTB
transformer
6 dB
attenuator
FILTER
N1
V_o
N2 V V'meas
57 MHz
RMS
voltmeter
modulation
analyzer
50 Ω
001aac098
V’_meas = V_o − (transformer ratio N1/N2 = 5 and loss).
Wanted signal source at f_RFpix is 70 dBµV.
The level of unwanted signal V_o at f_snd is measured by causing 0.3 % AM modulation in the wanted output signal.
N1 = 10 turns.
N2 = 2 turns.
N1/N2 = 5.
Fig 24. Cross modulation measurement in high band with symmetrical IF output
signal
50 Ω source
e
V_meas V
50 Ω
RMS
voltmeter
LBIN
or
IFOUTA
MBIN
DUT
27 Ω
spectrum
analyzer
50 Ω
IFOUTB
V_CCA
fce755
Z_i >> 50 Ω → V_i = 2 × V_meas.
V_i = V_meas + 6 dB.
Fig 25. Maximum RF input level without lock-out in low and mid band with asymmetrical IF output
signal
50 Ω source
A
C
e
V_meas V
50 Ω V_i
HYBRID
RMS
voltmeter
B
D
50 Ω
HBIN1
IFOUTA
DUT
HBIN2
IFOUTB
27 Ω
spectrum
analyzer
50 Ω
V_CCA
fce756
Loss in hybrid = 1 dB.
V_i = V_meas − loss.
Fig 26. Maximum RF input level without lock-out in high band with asymmetrical IF output
TDA6650ATT_6651ATT_2
Product data sheet
Rev. 02 — 2 February 2007
© NXP B.V. 2007. All rights reserved.
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