TDA5744 Datasheet, PDF (10/20 Pages) NXP Semiconductors – Low power mixers/oscillators for hyperband tuners

Philips Semiconductors
Low power mixers/oscillators for
hyperband tuners
Preliminary specification
TDA5744; TDA5745
handbook, full pagewidth
Vmeas V
50 Ω
unwanted
signal
50 Ω source
AC
AM = 30%
eu
HYBRID
RMS
voltmeter
VHFIN IFOUT1
Vi
D.U.T.
T
(1)
Vo
N1
C
(2)
N2
FILTER
18 dB
attenuator
38.9 MHz
V ^V'meas
modulation
analyzer
50 Ω
50 Ω
BD
wanted
ew
signal
source
50 Ω
IFOUT2
RMS
voltmeter
MGL275
(1) N1 is 2 × 5 turns.
(2) N2 is 2 turns.
Z_i >> 50 Ω ⇒ V_i = 2 × V_meas; V’_meas = V_o − 16 dB (transformer ratio ^NN-----12-- = 5 and transformer loss).
Wanted input signal V_i = 80 dBµV at wanted f_RF = 45.25 MHz (399.25 MHz).
Measured level of the unwanted output signal V_ou causing 1% AM modulation in the wanted output signal;
unwanted f_RF = 50.75 MHz (404.75 MHz); V_ou = V’_meas + 16 dB.
Fig.6 Cross modulation measurement in the VHF band.
handbook, full pagewidth
Vmeas V
50 Ω
unwanted
signal
50 Ω source
AC
AM = 30%
eu
HYBRID
RMS
voltmeter
AC
Vi
HYBRID
50 Ω
B
wanted
ew
signal
source
D
50
Ω
BD
50
Ω
UHFIN1 IFOUT1
D.U.T.
T
(1)
(2)
Vo ^N1
N2
C
FILTER
18 dB
attenuator
38.9 MHz
V
UHFIN2 IFOUT2
RMS
voltmeter
modulation
analyzer
50 Ω
MGL276
(1) N1 is 2 × 5 turns.
(2) N2 is 2 turns.
V_i = V_meas; V’_meas = V_o − 16 dB (transformer ratio ^NN-----12-- = 5 and transformer loss).
Wanted input signal V_i = 70 dBµV at f_RF = 407.25 MHz (855.25 MHz).
Measured level of the unwanted output signal V_ou causing 1% AM modulation in the wanted output signal;
unwanted f_RF = 412.75 MHz (860.75 MHz); V_ou = V’_meas + 16 dB.
Fig.7 Cross modulation measurement in the UHF band.
1998 Mar 09
10