TDA6142 SIEMENS | Alldatasheet
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BSE D MM 8235605 0053760 577 MMSIEG eee eee _ STEMENS AKTIENGESELLSCHAF j SAT-IF-Demodulator TDA 6142X P Preliminary Data Bipolar IC Features “| @ Good C/N response through high input sensitivity © Reduced noise bandwidth of prescaler at 480MHz . through LC circuit © Limiting of internal bandwidth of prescaler at 960 MHz ia @e © Improved stability against oscillation through LC circuit NG © High frequencies are damped and interference is reduced 5 osose by LC circuit | @ Enhanced AFC circuit with good thermal stability P-DSO-20 | @ Integrated input selector for dual SAW filter — —______! Type Ordering Code | Package TDA 6142x 6700-5046 __| P-DSO-20 (SMD) : Amplifier and IF demodulator for satellite applications, consisting of: four-stage limiter amplifier with selectivity circuit and selector switch for two IF-inputs, each with a base stage; divider by 4; video amplifier; automatic gain control; AFC-output with adjustable rate of rise; polarity switchover of video signal. Application In satellite receiving systems. 50 10.92
65E D MM 4235605 0053761 4O3 MMSIEG SIEMENS TDA 142K _ SSTEMENS AKTIENGESELLSCHAF Pin Definitions and Functions Pin No. Function
1 Connection of parallel-resonant circuit
2 Connection of parallel-resonant circuit —
3 AGC-voltage output OO oO
4 Setting of AGC threshold oO
& | Connection of resonant circuit for demodulator
6 Connection of resonant circuit for demodulator -
7 Ground
8 AFC-preamplifier output
9 AFC-lowpass filter and feedback point for AFC-sensitivty setting
10 ‘AFC-output to A/D-converter and AFC-lowpass filter
11 Video output
12 Video polarity switching, positive/negative —
13 \\F-reference input 2 _ a
14 IFinput2,egaf=27MHz
15 Reference voltage output —— —_
16 ~~} IF-input selector for IF-input 1 or 2 —
7 IF-reference input 1
18 IF-input 1, eg af= 18 MHz
19 Supply voltage 5 V
20 ‘AGC-lowpass filter Semiconductor Group 51
6SE D MM 8235605 OO537b2 34T MBSIEG SIEMENS SIEMENS AKTIENGESELLSCHAF © TDA6142K { Video { AGC Lowpass IF 1 Lin Output i Imput IF imput Video P/N ; LT Vs Af =48MHz switch Vacs A= 27MHz Switching ||. + —1t +4 | Limiter Amplifler with | IF ~ Imput Selector | saan ‘ ) Demodulator [=e * | i i 2 13 4 [5 (6 7 fee |? me | 10 | AGE PA A6c can ee Output fd Thereshats TF oP-Amp | setectivity Phase ~ Shifter eNO AFC Circuit Circuit Lowopass ToA/D Converter veanvost Block Diagram . Semiconductor Group 52
BSE D MM 8235605 0053763 286 MSIEG Circuit Description The frequency-modulated satellite |F-signal is applied by way of a SAW-filter - with two balanced outputs and different bandwidth - to the two low-impedance, balanced inputs of the limiter amplifier. ‘One iF-input at a time can be through-connected by applying an external DC-voltage to the !F-input selector. Unbalanced operation is also possible by appropriate RF blocking of the balanced inputs, \\. but this entails higher noise levels. An external selectivity circuit in the penultimate amplifier stage produces good selectivity in the limiter amplifier and consequently better harmonics suppression. The output signal from this amplifier is fed to a divider, which divides the frequency by 4. Following this the signal is applied once direct and once with phase shift - produced by an external phase- shifter circuit - to a quadrature demodulator. The demodulated video signal is amplified and appears at the video output. The polarity of this demodulated video signal can be inverted by applying an external DC-voltage to the polarity- switching input. Parallel to this, the demodulated video signal is used for automatic frequency control (AFC). Here it is fed via a preamplifier to an inverting operational amplifier with an internal reference voltage. Any frequency offset that is present will show itself in the form of a changing DC voltage, which can be applied to an external A/D-converter. The rate of rise of the AFC and thus the gain of the operational amplifier can be set externally by a resistor network. The information for the field strength of the frequency-modulated satellite IF-signal appears both as a DC-voltage at the AGC-output and on the AGC-lowpass filter. The AGC-threshold can be varied with a potentiometer. The IF stage of the satellite tuner (TUA 2008X) or an input stage can be controlled in gain by way of the AGC-output. Semiconductor Group 53
6SE D MM 8235605 0053764 112 MBSIEG SIEMENS _ TDA 6142X nee GE SELLSCHAF STEMENS AKTIENGESEL : Absolute Maximum Ratings T,=010 70°C Parameter ee | Limit Values em | Remarks Supa whage fe jos Selectivity circuit Vi,2 [os __ AGC-output voltage Va 1 _| Open collector AGC-threshold input Vs jos 2 v Resonant-circuit inputs _ Vee -03 3 v Video P/N-switching Ve -03 v ‘AFC-amplifier Vo jos v Vide op Ce (Co Reference voltage [Mis 03° IF-input selector Vie 0.3 5 v AGC-lowpass filter Veo -03 5 v Junction temperature T 150 Storage temperature 125 Thermal resistance system-air | Rinsa ee ee Surge strength forall pins” | Vee» |-2000 [2000 |v‘ | Operating Range Supply voltage _ Vv, (45 55 OC«W‘'W 7 Input frequency range fis [800 700 MHz __ Ambient temperature Ts 70 c 7 1) Single discharge of 100-pF capacitor across series resistor of 1.5 kQ in turn on each pin (MIL-STD) 2) Float pins not required; pin 7 always ground Semiconductor Group 54
GSE D —__ = 8235605 005375 O55 MESIEG SIEMENS SIEMENS To TDA 6142X N. rE Nn ENS AR TIENGES ELL ee SCHAF Characteristics Ty = 25 C; Vg=5V 410% Parameter i Symbol Limit Values —_| Unit [Test Condition Current drain i 40 [50 60 [ma | Input Sensitivity IF input Tam [= 65 3 [dBm [fo.war. = i 480 MHz IF-Input Switching IF-input 4 Vie [32 5 | Vv IF-input 2 Yee 0 28 |v | Video Output Video voltage (4f=13.5MHz) [Vi | 400 js00 [mv —_ Distortion factor THD <1 1% Signalinoise ratio. SIN ~ 170 eB Video P/N-Switching Positive polarity Vio 35 v Input current Than | 50 pA, Negative polarity Vie 1 vj Input current Im i -50 [HA | AGC-Current (Open-collector current limited) pn = + 3 dBm iA 500 “WA [Vs=8V; Race = 0 ip =— 3 dBm ils 1 10 [WA | Ve=8V; Rago = 0 iy =~ 24 ABM ‘ly ‘ 500 | WA |Va=8V; Raac= = Gin =~ 30 dBm |b jo WA! Vs=8V; Rrac= AFC-Voltage (Open-collector current limited) ‘firin = 380 MHz Vio Ve | .V | RoR, =7 ‘Firm = 580 MHz Vio -05 05 |V_ |R/R,=7 Semiconductor Group 55
b5E D MM 8235605 O0537bb T95 MMSIEG : wo CSTE AKTIENGESELLSCHAF —— IF Signat Generator fe im B A B A ) Directional | gy Directional J osy vid C o Coupl 0 je0- j onFT | Tine on aan Output oa wr nF ink (A) Veet nF [tnF @) 20119 ae 16 dis [a Ke) (eee TDA 6142 X i 4.8 pF [ 202 | 68 ka 8v C+-t—1 18 pF AC Output A/0 Converter ‘UESO4052 Test Circuit 1 OO Semiconductor Group 56
65E D MM 4235605 0053767 Tel MESIEG SIEMENS AKTIENGESELLSCHAF i | | | Video- | SV= Input 4 syv=p Output | OV= Input 2 OV=N (5V) 10 pF soonF. | Tine sun | osu ae Od Fess i 20 19 18 a7 16 15 1h B L 12 kil | | 6 7 8 9 10 | 4.8 pF | 208 | ke | 6aKe ——o a
78 F AFC Output
i} to A/O Converter ‘ veses0s3 Application Circuit — OO Semiconductor Group 57
BSE D MM 6235605 00537b8 868 MMSIEG _SIEMENS_ TDA G42 SIEMENS AKTIENGESELLSCHAF ==) Diagram 1 UED04054 SEP se IN ATE ECE ERK ES Een eet A oJ pt tT | yey Tt i a a FS ee 430 450 470 490 510 MHz 530 Video Voltage Vay — IF Test Frequency mom AFC Voltage Yio Diagram 2 40 venouass ve el Ce S POPU Tr AT ee ee 5 of LT Fees ee a | 2S CPI eT { a 2 ee 2 | vo — ZT CCI PIP LO Ie) a a
9 LUI nh
— iF input Semiconductor Group 58