Video Modulator for FM/AM-Audio with PLL-Output TDA 5670-5X Preliminary Data Bipolar IC Features ● ● ● ● ● ● ● ● ● ● ● ● FM- and AM-audio modulator Symmetrical RF-oscillator output for PLL-control 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 P-DSO-20 -1 Type Ordering Code Package TDA 5670-5X Q67000-A5167 P-DSO-20-1 (SMD) TDA 5670-5X Q67006-A5167 P-DSO-20-1 Tape & Reel Functional Description and Application The monolitic integrated circuit TDA 5670-5X is especially suitable as a modulator for the 48- to 860-MHz frequency range. Video recorders, cable converters, TV-converter networks, demodulators, video generators, video security systems, amateur TV-applications and personal computers. Semiconductor Group 1 04.95 TDA 5670-5X Circuit Description Oscillator The RF-oscillator is available at pins 3-7. The oscillator operates as a symmetrical Colpitts circuit. The oscillator chip ground, pin 5, should be connected to ground at the resonance circuit shielding point. An external oscillator can be injected inductively or capacitively via pins 3 and 7. The layout of the PCB should be such as to provide a minimum shielding attenuation between the oscillator pins 3-7 and modulator output pins 15-17 of approximately 80 dB. 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 0o and 180o. 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 RFcarrier 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 be Q = 25 and the parallel resistor RT = 8.2 kΩ to ensure a video to audio carrier ratio of 12.5 dB. At the same time, the 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 AMmodulation 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. Source The internal reference voltage is available at pin 2 and has to be capacitively blocked there. Semiconductor Group 2 TDA 5670-5X Pin Configuration (top view) P-DSO-20-1 Semiconductor Group 3 TDA 5670-5X Pin Definitions and Functions Pin No. Symbol Function 1 FM-Audio AF-input for FM-modulation 2 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 8 VS Supply voltage (12 V) 9 N.C. Not connected 10 PLL-Out 1 Symmetrical unmodulated oscillator output 11 PLL-Out 2 Symmetrical unmodulated oscillator output 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 AM-modulation 19 FM-Audio OSC FM-audio oscillator; symmetrical inputs for tank circuit 20 FM-Audio OSC FM-audio oscillator; symmetrical inputs for tank circuit Semiconductor Group 4 TDA 5670-5X Block Diagram Semiconductor Group 5 TDA 5670-5X Absolute Maximum Ratings TA = 0 to 70 oC Parameter Symbol Limit Values min. typ. Unit Remarks max. Supply voltage pin 8 VS – 0.3 14.5 V Current from pin 2 –I2 0 2 mA Voltage at pin 1 Voltage at pin 2 Voltage at pin 12 V1 V2 V10 0 6 0 2 8.5 1.5 V V Vpp Capacitance at pin 2 Capacitance at pin 13 C2 C13 0 0 100 15 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 V2 V2-1.5 1.4 VS VS V2+1.5 V V V V V2 = 7...8 V VS = 10...13.5 V only via C (max. 1 µF) VS = 10-13.5 V According to the application circuit, only the provided circuitry can be connected to pins 3,4,6,7,10,11,19 and 20. Junction temperature Tj Storage temperature Tstg Thermal resistance Rth – 40 150 oC 125 oC 125 K/W The pins 3, 4, 6 and 7 are not protected against voltage stress. The high frequency performance prohibits the use of adequate protective structures. Operating Range Supply voltage VS 10 13.5 V Video input frequency fVideo 0 6 MHz Audio input frequency fAF 0 20 kHz Output frequency fQ 30 860 MHz Ambient temperature TA 0 70 oC Audio oscillator fOSC 4 7 MHz Voltage at pin 2 Voltage at pin 15,17 V2 V15, 17 6.75 V2 7.75 VS V V Semiconductor Group 6 depending on the oscillator circuitry at pins 3-7 TDA 5670-5X AC/DC-Characteristics TA = 25 oC; VS = 12 V Parameter Symbol Limit Values Unit Test Condition Test Circuit min. typ. max. 22 28 34 mA I2 = 0 mA 1 6.75 7.25 7.75 V 0 ≤ I2 ≤ 1 mA 1 900 MHz VD = 0...28 V 1 t = 5 s-15 min. after switching on 1 ∆T = 25 oC 1 VS = 12 V ± 10% TA = const.; Ch 40 Source Current consumption I8 Reference voltage V2 Oscillator 470 Oscillator frequency range fOSC Oscillator drift ∆fOSC 200 kHz ∆fOSC ∆fOSC 800 400 kHz kHz Oscillator level α10;11 –20 –20 dBm dBm Ch 21 Ch 69 Oscillator output impedance R10; R11 200 Ω 1 C10; C11 2 pF parallel equivalent circuit parallel equivalent circuit RF-output imp. RF-output imp. Z15; Z17 C15 = C17 0.5 150 1 static 2.0 1 1 RF-output voltage VQ 2.5 4.5 5.5 mVrms Ch 40; video 100% white; without audiosignal 1 RF-output phase α15, 17 140 180 220 deg RF-output voltage changes ∆VQ 0 1.5 dB f = 470-900 MHz dB fVC + 1.07 MHz 2 dB fVC + 8.8 MHz without video 2 Intermodulation ratio αIMR 50 Harmonic wave ratio αO 35 Semiconductor Group 75 7 Ω pF 1 TDA 5670-5X AC/DC-Characteristics (cont’d) TA = 25 oC; VS = 12 V Parameter Symbol Limit Values min. typ. Unit max. Test Condition Test Circuit Unmodulated video and audio carrier, measured with the spectrum analyzer as difference between video carrier signal level and sideband signal level; loaded Q factor QL of the audio oscillator resonance circuit adjusted by RP to provide the required video to audio carrier ratio of 12.5 dB; QU = 25 Video to audio carrier ratio αV/A 10 12.5 Harmonic wave ratio αO 35 Harmonic wave ratio αO 42 15 dB fVC+fAC (5.5 MHz) 1 48 dB 48 dB fVC + 2 fAC (11 MHz) fVC + 3 fAC (16.5 MHz) 1 1 All remaining harmonic waves; multiple of fundamental wave of video carrier, without video signal, measured with spectrum analyzer; fVC = 523.25-623.25 MHz; pin 14 open α 15 dB Residual carrier suppression αR 32 dB Ch 30...40 3 Signal-to-noise in video; unmodulated audio carrier αN/V 48 74 dB Ch 30...40 4 αA/V 49 62 dB Ch 30...40, 4 FM-modulation of audio carrier αA/V 48 60 dB Ch 30...40 mA = 90% 4 Unweighted AM- αV/A 48 54 dB 5 Unweighted FMinterference level ratio video in audio αV/A 48 54 dB Ch 39; test picture FuBK Ch 39; test picture FuBK Signal-to-noise ratio of audio oscillator αN/A αN/A 48 48 54 54 dB dB AM unmodulated FM-audio carrier 5 5 Video input current at pin 12 –I12 0 1 µA C12 ≤ 100 nF 1 Video input voltage at pin 12 V12 0.7 1.4 Vpp C12 ≤ 100 nF 1 Interference product ratio audio in video AM-modulation 1 5 Video Semiconductor Group 8 TDA 5670-5X AC/DC-Characteristics (cont’d) TA = 25 oC; VS = 12 V Parameter Symbol Limit Values Unit Test Condition Test Circuit min. typ. max. 60 70 80 % staircase signal at video input; VVideo = 1 Vpp 6 6 6 Modulation depth mD/N Stability of mod. depth ∆mD 1 ± 2.5 % ∆mD 1 ± 2.5 % ∆VVideo = 1 Vpp ± 3 dB; TA = 0-60 oC ∆mD 1 ± 2.5 % VS = 10-13.5 V Differential gain αdif 10 % Differential phase Φdif 15 deg 6 7 measured with measurement demodulator, video test signals and vector scope 7 Amplitude response of video signal; VVideo = 1 Vpp with additional modulation f = 15 kHz-5MHz sine signal between black and white αV 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 6 t 50 µs C at pin 13 = 10 µF; I leakage ≤ 2 µA 1 Setting time for video signal change from 0 Vpp to 1.4 Vpp; video blanking signal content is uniform white level 120 t 500 µs 1 Setting time for video blanking signal from 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; unloaded Q factor of resonance circuit Qu = 25; fresonance = 5.5 MHz fA/OSC Semiconductor Group 4 7 9 MHz 1 TDA 5670-5X AC/DC-Characteristics (cont’d) TA = 25 oC; VS = 12 V Parameter Symbol Limit Values min. typ. Unit max. Test Condition Test Circuit 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 Audio signal frequency deviation ∆ fA/OSC 5 15 kHz TA = const.; 1 ∆ fA/OSC 5 10 kHz VS = 10.0-13.5 V; Qu = 25 1 30 40 % VAF = 45 mVrms 9 0.5 3 % m = 80%; VAF = 117 mVrms fAF = 1 kHz 9 50 75 kΩ 1 AM-Audio AM-mod. factor m 20 AM-mod.; total harmonic distortion THDAM Audio preamplifier input impedance Z16 AM-audio modulator input voltage VAF 132 mVrms m = 90%; fAF = 1 kHz 9 Residual carrier FM; AM-operation ∆f 20 Hz without AM-audio signal QU = 25 1 FM-mod.; total harmonic distortion THDFM 0.6 1.5 % V1 = 150 mVrms 9 FM-mod.; static mod. characteristic ∆ fA/OSC ± 50 ± 70 ± 90 kHz ∆VAF= V1-V2 = ±1V 1 FM-mod.; dynamic mod. characteristic ∆ fA/OSC/ ∆VAF 0.08 0.10 0.13 kHz/ mV 1 Audio preamplifier input impedance (dynamic) Z1 200 kΩ 1 25 FM-Audio Semiconductor Group 10 TDA 5670-5X Test Circuit 1 Test and Measurement Circuit for AM- and FM-Audio Carrier and Negative Video Modulation Semiconductor Group 11 TDA 5670-5X Test Circuit 2 Description of the Measurement Configuration to Measure the 1.07-MHz 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. f VC = 623.25 MHz Semiconductor Group 12 TDA 5670-5X Test Circuit 3 Description of the Measurement Configuration to Measure the Residual Carrier Suppression Semiconductor Group 13 TDA 5670-5X Test Circuit 4 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 measurement 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 x 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. Semiconductor Group 14 TDA 5670-5X Test Circuit 5 Description of the Measurement Configuration to Measure the Video and/or Noise in Audio Calibration: Measuring: AF-signal of f = 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. 1) The AF-signal is switched off and the FuBK-video signal is connected to the video input with Vvid = 1 Vpp. The audio level in relation to the AF-reference calibration level is measured as ratio aV/A. 2) AF- and video signal are switched off. The noise ratio in relation to the AFreference calibration level is measured as signal-to-noise ratio in the audio signal aN/A. Semiconductor Group 15 TDA 5670-5X Test Circuit 6 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 Vvid = 1 Vpp is connected to the video input. Measuring: 1) Modulation depth mD/N for negative modulation: pin 14 open, range peak white value – sync level in relation to range zero reference – sync level gives mD/N. 2) Modulation depth mD/P for positive modulation: pin 14 to ground, range peak white value – sync level in relation to range zero reference – peak white value gives mD/P. Semiconductor Group 16 TDA 5670-5X Test Circuit 7 Description of the Measurement Configuration to Measure the Differential Gain and Phase Semiconductor Group 17 TDA 5670-5X Test Circuit 8 Description of the Measurement Configuration to Measure the Video Amplitude Response Semiconductor Group 18 TDA 5670-5X Test Circuit 9 Description of the Measurement Configuration to Measure the Harmonic Distorsion Factor and AM-Input Voltag Semiconductor Group 19 TDA 5670-5X Application Circuit Semiconductor Group 20 TDA 5670-5X Diagram Function of Video Signal Connection a) Demodulated RF-output video signal V15/17rms = f (V12rms); fmod = 16 kHz b) V13 = f (V12rms) Semiconductor Group 21 TDA 5670-5X GPS05094 Plastic Package, P-DSO-20-1 (SMD) (Plastic Dual Small Outline Package) Sorts of Packing Package outlines for tubes, trays etc. are contained in our Data Book “Package Information” SMD = Surface Mounted Device Semiconductor Group 22 Dimensions in mm