TDA6500 Datasheet, PDF (27/37 Pages) NXP Semiconductors – 5 V mixer/oscillator and synthesizer for PAL and NTSC standards

Philips Semiconductors
TDA6500; TDA6501
5 V mixer/oscillator and synthesizer for PAL and NTSC standards
13.2 Test circuit for low band measurements
signal
50 Ω source
e
V_meas V
LBIN
IFOUT
50
Ω
V_i
DUT
C
V_o
L
V'_meas
spectrum
analyzer
50 Ω
RMS
voltmeter
Z_i >> 50 Ω → V_i = 2 × V_meas = 80 dBµV
V_i = V_meas + 6 dB = 80 dBµV
V_o = V’_meas × --------------⁵---⁰-------------- = V’_meas + attenuation
50² + L²Ï‰²
G_v = 20 log ^V-_V----^o-_i
PAL: IF = 38.9 MHz; L = 680 nH; C = 25.9 pF and attenuation = 10.2 dB
Fig 8. Gain (G_V) measurement in low band
fce213
I1
PCB
BNC ^C1
I3
PCB
BNC ^C3
plug
L1
C2
RIM-RIM
001aad065
I2
C4
plug
RIM-RIM
mbe286
a. f_RF = 50 MHz
b. f_RF = 150 MHz
Low band mixer frequency response
measured = 57 MHz; loss = 0 dB;
image suppression = 16 dB.
C1 = 9 pF.
C2 = 15 pF.
L1 = 7 turns (∅ 5.5 mm,
wire ∅ = 0.5 mm).
l1 = semi rigid cable (RIM): 5 cm long;
33 dB/100 m; 50 Ω; 96 pF/m
Low band mixer frequency response
measured = 150.3 MHz;
loss = 1.3 dB;
image suppression = 13 dB.
C3 = 5 pF.
C4 = 25 pF.
l2 = semi rigid cable (RIM): 30 cm
long; 33 dB/100 m; 50 Ω 96 pF/m.
l3 = semi rigid cable (RIM): 5 cm long;
33 dB/100 m; 50 Ω 96 pF/m.
Fig 9. Input circuit for optimum noise figure in the low band
9397 750 15057
Product data sheet
Rev. 02 — 14 June 2005
© Koninklijke Philips Electronics N.V. 2005. All rights reserved.
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