TDA6508 Datasheet, PDF (26/42 Pages) NXP Semiconductors – 3-band mixer/oscillator and PLL for terrestrial tuners

Philips Semiconductors
3-band mixer/oscillator and PLL for
terrestrial tuners
Product specification
TDA6508; TDA6508A;
TDA6509; TDA6509A
handbook, full pagewidth
signal
50 Ω source
e
Vi(meas) _V
50 Ω
RMS
voltmeter 50 Ω
A
C
HYBRID
B
D
MID_RFIN1
IFAMP_OUT1
27 Ω
Vi _D.U.T.
MID_RFIN2
Vo Vo(meas)
spectrum
analyzer
50 Ω
MDB260
Z_i >> 50 Ω symmetrical input.
Hybrid loss = 1 dB.
V_i = V_i(meas) − loss + 6 + 3 = 80 dBµV.
V_o = V_o(meas) + 3.75 dB.
G_v = 20 log -VV----^o-_i
PAL f_IF = 36.15 MHz.
Fig.18 Gain measurement in the MID-band of the TDA6508A; TDA6509A.
handbook, full pag^ueⁿw^widt^ah^nted
signal
50 Ω _source
AC
AM = 30%
eu
HYBRID
AC
Vi
HYBRID
50 Ω
wanted ^B
ew signal
source
D
50
Ω
BD
50
Ω
MID_RFIN1
IFAMP_OUT1
D.U.T.
IFAMP_OUT2
MID_RFIN2
Vo
2x5
turns
FILTER
18 dB
attenuator
38.9 MHz
2
V ^Vo(meas)
turns
N1/N2 = 5 RMS
voltmeter
modulation
analyzer
50 Ω
MDB253
V_o = V_o(meas) + 15 dB (transformer ratio N1/N2 and transformer loss).
Wanted output signal at picture carrier frequency f_RF(w); V_o(w) = 110 dBµV.
Unwanted output signal at sound sub-carrier frequency f_RF(u); AM = 30%; AF = 2 kHz.
Measuring the level of unwanted signal causing 0.3% AM in the wanted signal.
f_RF(w) = 154.25 MHz (min.); 447.25 MHz (max.).
f_RF(u) = 159.75 MHz (min.); 452.75 MHz (max.).
f_osc = 193.15 MHz (min.); 486.15 MHz (max.).
Fig.19 Cross-modulation measurement in the MID-band of the TDA6508; TDA6509.
2005 Mar 25
26