MGM3000X SIEMENS | Alldatasheet
Document overview
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Technical content
Features
- FM- and AM-audio modulator
- Audio carrier output for suppression of harmonics
- Sync level clamping of video input signal
- Controlling of peak white value
- Continuous adjustment of modulation depth for positive or negative values
- Symmetrical mixer output with separate ground area
- Symmetrical oscillator with separate RF-ground
- Low spurious radiation
- High stability of the RF-oscillator frequency
- High stability of the audio oscillator
- Internal reference voltage
- 12 V supply voltage Semiconductor Group 1 12.94
For optimal residual carrier suppression, the symmetrical mixer outputs at pins 15, 17 should be connected to a matched balanced-to-unbalanced broadband transformer, e.g. a Guanella transformer with good phase precision at 0° and 180°. The transmission loss should be less than 3 dB. In addition, an LC-low pass filter combination is required at the output. The cut-off frequency of the low pass filter combination must exceed the maximum operating frequency. Video The video signal with the negative synchronous level is capacitively connected to pin 12. The internal clamping circuit is referenced to the synchronizing level. Should the video signal change by 6 dB, this change will be compensated by the resonance circuit which is set by the peak white value. At pin 13, the current pulses of the peak white detector are filtered through the capacitor which also determines the control time constant. The RF-carrier switches from negative to positive video modulation, when pin 14 is connected to ground. By varying the value of resistance R at pin 14 between∞ …0 Ω the modulation depth can be increased from 70 % to 100 % when the modulation is negative and decreased from 100 % to 70 % when the modulation is positive. Audio Via pin 1, the audio signal is capacitively coupled to the AF-input for the FM-modulation of the oscillator. A parallel resonance circuit is connected to the audio carrier oscillator at pins 19, 20. The unloaded Q of the resonant circuit must beQ = 25 and the parallel resistorRT = 6.8 kΩ to ensure a video to audio carrier ratio of 12.5 dB. At the same time, capacitative and/or inductive reactance for the resonance frequency should have a value of XC ≈ XL ≈ 800 Ω. Via pin 18, the audio signal is capacitively coupled to the AF-input for the AM-modulation of the oscillator. This signal is forwarded to a mixer which is influenced by the AM- modulation input of pin 18. The video to audio carrier ratio can be changed by connecting an external voltage to pin 18, which deviates from the internal reference voltage. Through an additional external dc voltage at pin 18, the set AM-modulation index can be changed by overriding the internally adjusted control voltage for a fixed AM-modulation index. At the output of the above described mixer the FM and/or AM modulated audio signal is added to the video signal and mixed with the oscillator signal in the RF-mixer. For optimal suppression of harmonics of the audio carrier an audio filter should be connected between pin 10 and 11. Source The internal reference voltage is available at pin 2 and has to be capactively blocked there.
(top view)
Pin Definitions and Functions Pin No. Symbol Function
1 FM-Audio AF-input for FM-modulation
VREF Internal reference voltage (7.5 V)
3 OSC-Input 1 Symmetrical oscillator input
4 OSC-Out 1 Symmetrical oscillator output
5 OSC-Ground Oscillator ground
6 OSC-Out 2 Symmetrical oscillator output
7 OSC-Input 2 Symmetrical oscillator input
VS Supply voltage (12 V) 9 N.C. Not connected
10 Audio Out 1 Audio output; symmetrical inputs for audio filter
11 Audio Out 2 Audio output; symmetrical inputs for audio filter
12 Video Video input with clamping
13 Video-Cap. Connection for smoothing capacitor for video control loop
14 Modulation Switch-over for positive and negative modulation
15 Output 2 Symmetrical RF-output
16 Ground Ground
17 Output 1 Symmetrical RF-output
18 AM-Audio Video to audio carrier ratio adjustment and AF-input for
19 FM-Audio OSC FM-audio oscillator, symmetrical inputs for tank circuit
20 FM-Audio OSC FM-audio oscillator, symmetrical inputs for tank circuit
TA = 0 to 70°C Parameter Symbol Limit Values Unit Remarks min. typ. max. Supply voltage pin 8VS − 0.3 14.5 V Current from pin 2 − I2 0 2m A V2 = 7-8 V, VS = 10-13.5 V Voltage at pin 1 Voltage at pin 2 Voltage at pin 12 V10 8.5 1.5 V V Vpp only via C (max.1µF) Capacitance at pin 2 Capacitance at pin 13 C 2 C 13 100 nF µF Voltage at pin 14 Voltage at pin 15 Voltage at pin 17 Voltage at pin 18 V14 V15 V17 V18 − 0.3 V2 − 1.5 1.4 13.5 13.5 V2 + 1.5 V V V V VS = 10-13.5 V According to the application circuit, only the provided circuitry can be connected to pins 3, 4, 6, 7, 10, 11, 18 and 20. Junction temperatureTj 150 °C Storage temperature Tstg – 40 125 °C Thermal resistance Rth 80 K/W Operating Range Supply voltage VS 10 13.5 V Video input frequencyfVideo 0 6 MHz Audio input frequencyfAF 0 20 kHz Output frequency fQ 30 860 MHz depending on the oscillator circuitry at pins 3-7 Ambient temperature TA 08 0 °C
Audio oscillator fOSC 4 7 MHz Voltage at pin 2 Voltage at pin 15, 17 V15, 17 7.50 VS V V AC/DC Characteristics T A =2 5°C; VS =1 2V Parameter Symbol Limit Values Unit Test Condition Test Circuit min. typ. max. Source Current consumption Current consumption I15 + I17 2.0 2.6 3.4 mA mA I2 = 0 mA 1 Reference voltage V2 7.00 7.25 7.50 V 0 ≤ I2 ≤ 1m A 1 Oscillator Oscillator frequency range fOSC 30 860 MHz external circuitry adjusted to frequency Switch-on, warm up drift TC-value of capacitor in osc. circuit is 0; drift is referenced only to selfheating of the component. Δ fOSC –5 0 – 200 – 500 – 500 kHz kHz t= 0.5-10 s; TA = const. Ch 30 Ch 40 Frequency drift as function of VS ΔfOSC – 150 150 kHz VS = 10-13.5 V TA = const.; Ch 40 RF-output impedance R15;R17 C 15;C 17 0.5 1 2.0 kΩ pF parallel equivalent circuit parallel equivalent circuit Absolute Maximum Ratings (cont’d) TA =0t o7 0°C Parameter Symbol Limit Values Unit Remarks min. typ. max.
RF-output voltage VQ 2.5 4.5 5.5 mVrms Ch 60; video 100 % white; without audio- signal RF-output phase a15, 17 140 180 220 deg RF-output voltage changes ΔVQ ΔVQ ΔVQ 1.5 1.5 1.5 dB dB dB f= 743.25-
823.25 MHz
Δ f= 80 MHz; Ch 55-65 f= 100-300 MHz f= 48-100 MHz Intermodulation ratioaIMR 60 75 dB fVC + 1.07 MHz fVC + 1.57 MHz fVC + 2.07 MHz Harmonic wave ratioaO 60 dB fVC + 8.8 MHz fVC + 13.29 MHz fVC + 17.72 MHz, without video 13, 14, 15 unmodulated video and audio carrier, measured with the spectrum analyzer as difference between video carrier signal level and sideband signal level; loadedQ factorQ L of the audio oscillator resonance circuit adjusted byRP to provide the required video to audio carrier ratio of 12.5 dB;Q U = 25. Video to audio carrier ratio aV/A 10 12.5 15 dB fVC + fAC (5.5 MHz) 1 Harmonic wave ratio Harmonic wave ratio aO aO dB dB fVC +2 fAC (11 MHz) fVC +3 fAC (16.5 MHz) AC/DC Characteristics (cont’d) TA =2 5°C; VS =1 2V Parameter Symbol Limit Values Unit Test Condition Test Circuit min. typ. max.
harmonic waves; multiple of funda- mental wave of video carrier, without video signal, measured with spectrum analyzer; fVC = 523.25-
623.25 MHz; pin 14
open. a 15 dB 1 Residual carrier suppression aR 32 dB Ch 30 … 40 3 Signal-to-noise in video; unmodulated audio carrier aN/V 48 74 dB Ch 60 4 Interference product ratio audio in video AM-modulation FM-modulation of audio carrier aA/V aA/V dB dB Ch 60; m A =9 0% Ch 60;± 35 kHz Unweighted AM Unweighted FM Interference level ratio video in audio aV/A aV/A dB dB Ch 39; test picture FuBK Ch 39; test picture FuBK Signal-to-noise ratio of audio oscillator aN/A aN/A dB dB AM unmodulated FM video carrier Video Video input current at pin 12 –I12 01 µA C 12 ≤ 100 nF 1 Video input voltage at pin 12 V12 0.7 1.4 Vpp C 12 ≤ 100 nF 1 AC/DC Characteristics (cont’d) TA =2 5°C; VS =1 2V Parameter Symbol Limit Values Unit Test Condition Test Circuit min. typ. max.
video input; VVideo = 1 Vpp Stability of mod. depth Stability of mod. depth Stability of mod. depth Δ m D Δm D Δm D ± 2.5 ± 2.0 ± 2.0 Δ VVideo = 1 Vpp± 3 dB; TA = 0-60°C VS = 10-13.5 V Differential gain adif 10 % 7 Differential phase Φ dif 15 deg measured with measurement demodulator, video test signals and vector scope Amplitude response of video signal; VVideo = 1 Vpp with additional modulation f= 15 kHz-5 MHz sine signal between black and white. aV 0 1.5 dB 8 Period of time required for peak white detector to reach steady state for full modulation depth with 1-white pulse per half frame when control is already in the steady state. t 65 0 µs C at pin 13 = 10µF Ileakage≤ 2 µA Setting time for video signal change from 0 Vpp to 1.4 Vpp, video blanking signal content is uniform white level. t 120 500 µs1 AC/DC Characteristics (cont’d) TA =2 5°C; VS =1 2V Parameter Symbol Limit Values Unit Test Condition Test Circuit min. typ. max.
100 % white level to 42 % grey level with subsequent rise in grey level to 71 % of video blanking signal (due to decontrol process). t 0.4 2 10 min 1 Audio Audio oscillator frequency range; unloadedQ factor of resonance circuit Q U = 25; fresonance= 5.5 MHz. fA/OSC 4 7 MHz 1 Switch-on, warm-up drift of oscillator frequency; TC-value of capacitor in audio oscillator circuit is 0, the drift is only based on self-heating of component. Δ fA/OSC 5 kHz TA = const.; > 5 s after switching on Audio signal frequency devitation ΔfA/OSC 5 kHz VS =1 2V ± 10 % Q U =2 5 AM-Audio AM-mod. factor m 50 70 % VAF = 90 mVrms 9 AM-mod.; total harmonic distortion THD AM 0.5 3 % m =8 0% ; VAF = 117 mVrms; fAF = 1 kHz Audio preamplifier input impedance Z18 25 50 75 k Ω 1 AC/DC Characteristics (cont’d) TA =2 5°C; VS =1 2V Parameter Symbol Limit Values Unit Test Condition Test Circuit min. typ. max.
VAF 132 mVrms m =9 0% ;fAF = 1 kHz 9 Residual carrier FM; AM-operation Δf 20 Hz without AM-audio signalQ U =2 5 FM-Audio FM-mod.; total harmonic distortion THD FM 0.6 1.5 % V1 = 150 mVrms 9 FM-mod.; static mod. characteristic ΔfA/OSC ± 150 ± 210 ± 270 kHz ΔVAF = V1 – V2 = ± 1V 1 FM-mod.; dynamic mod. characteristic ΔfA/OSC/ ΔVAF 0.30 0.25 0.36 0.33 0.36 0.30 0.44 kHz/mV kHz/mV kHz/mV BIN 1 BIN 2 BIN 3 Audio preamplifier input impedance (dynamic); FM-operation Z1 200 k Ω 1 Overshoot Overshoot 1 % 15-kHz video signal AC/DC Characteristics (cont’d) TA =2 5°C; VS =1 2V Parameter Symbol Limit Values Unit Test Condition Test Circuit min. typ. max.
Test and Measurement Circuit for AM- and FM-Audio Carrier and Negative Video Modulation
Description of the Measurement Configuration to Measure the Moire CC-level lies below the activation point and has been set to provide a ratio of 17 dB with respect to the video carrier. fVC = 623.25 MHz
Description of the Measurement Configuration to Measure the Residual Carrier Suppression
Description of the Measurement Configuration to Measure the Audio and/or Noise in Video during FM- and AM-Modulation of the Audio Carrier Calibration:AF-signals are switched off, video signal is present at video input, modulation measure- ment device set at AM is adjusted to video carrier; filter: 300 Hz … 20 kHz; detector: (P + P)/2; Wave analyzer at video signal level (16 kHz) adjusted and resultant level as reference aV defined. 1. Measurement of audio interference product ratio in video while the audio carrier FM modulated: AF-signal is connected to FM-audio input; video signal is present at video input; Modulation measurement device set at AM; filter: 300 Hz … 20 kHz; detector: (P + P)/2; the automatic RF-level position of the measurement device is switched off; wave analyzer at video signal level 1 kHz or 2 kHz or 3 kHz adjusted and resultant level is set to aA. The audio noise ratio in video results from aA/V =aA – aV (dB). 2. Measurement of signal-to-noise ratio in video without FM-modulation of audio carrier: AF-signals are switched off; video signal is switched on; modulation measurement device set at AM; filter: 300 Hz … 3 kHz; detector; RMS×√ 2; Wave analyzer at video signal level (16 kHz) detuned; read out in dB to reference level of calibration is aN/V; 3. The noise limit of the measurement device is approx. 85 dB.
Description of the Measurement Configuration to Measure the Video and or Noise in Audio Calibration: AF-signal off= 1 kHz, corresponding with a nominal deviation of 30 kHz, is connected to the audio input, and the demodulated AF-reference level at the audio measurement device is defined as 0 dB. No video signal is present. Measuring: 1. The AF-signal is switched off and the FuBK-video signal is connected to the video input with VVideo = 1 Vpp. The audio level is relation to the AF-reference calibration level is measured as ratioaV/A. 2. AF-and video signals are switched off. The noise ratio in relation to the AF-reference calibration level is measured as signal-to-noise ratio in the audio signalaN/A.
Description of the Measurement Configuration to Measure the Modulation Depth for Positive and Negative Modulation Calibration: A zero reference signal with the TV measuring receiver is given to the video signal. A video signal with VVideo = 1 Vpp is connected to the video input. Measuring: 1. Modulation depthm D/N for negative modulation: pin 14 open, range peak white value-sync level in relation to range zero reference-sync level givesm D/N. 2. Modulation depthm D/P for positive modulation: pin 14 to ground, range peak white value-sync level in relation to range zero reference-peak white value givesm D/P.
Description of the Measurement Configuration to Measure the Differential Gain and Phase
Description of the Measurement Configuration to Measure the Video Amplitude Response
Description of the Measurement Configuration to Measure the Harmonic Distorsion Factor and AM-Input Voltage
Function of Video Signal Connection. a) Demodulated RF-output video signal V15/17rms = f(V12rms);fmod = 16 kHz b)V13 = f(V12rms)
Plastic Package, P-DSO-20-1 (SMD) (Plastic Dual Small Outline) GPS05094 Sorts of Packing Package outlines for tubes, trays etc. are contained in our Data Book “Package Information” Dimensions in mmSMD = Surface Mounted Device