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U4935B SECAM Decoder Description The U4935B is an SECAM decoder designed for use with the PAL/NTSC TV baseband processor U4930B and the baseband delay line U3665M. The circuit includes a bell filter, a demodulator and an identification circuit. A signal with stable reference frequency for calibration and a three-level sandcastle pulse for blanking and burst gating are required. The IC is realized in a bipolar VLSI technology and operates with +8 V supply voltage. Easy interfacing and few external components support the design of a multistandard TV. Features D Fully integrated and auto-tuned filters D Minimum number of external components D Easy interfacing with the TV baseband processor and the switched capacitor baseband delay line Package 16-pin dual in-line plastic (DIP16) Block Diagram VS = 8 V 0.1 m F Bell filter out 2 CVBS 16 in Bell filter ref 7 PLL auto2 12 PLL auto1 13 0.1 m F 3 Bandgap AMP PLL B -Y output SECAM sw. R -Y output 10 - (B-Y) out 9 - (R-Y) out 4 Band gap 22 m F ACC Bell filter Bell-filter tuning Ident De- emphasis Interface PLL tuning 5 Killer out 0.47 m F 8 PLL ref Pulse gen. 15 SCP in 6 GND 14 Black adj. R 11 Black adj. B 96 11715 1 fref/ ident Figure 1. Block diagram Ordering Information Extended Type Number U4935B-ADP Package DIP16 Remarks TELEFUNKEN Semiconductors Rev. A1, 28-Jan-97 1 (16) Preliminary Information U4935B Pin Description Pin 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 fref / ident Bell-filter output 8-V supply voltage Band-gap reference voltage SECAM killer output Ground Bell-filter reference voltage output PLLref PLL reference -(R-Y) -(R-Y) output -(B-Y) -(B-Y) output Black adj. B Black level adjust B - channel PLL1 PLL auto 2 PLL2 PLL auto 1 Black adj. R Black-level adjust R - channel SCP Sandcastle pulse input CVBS CVBS input Symbol fref / ident Bell out VS Band gap Killer out GND Bellref Function fref / ident Bell filter output VS 1 16 CVBS input 2 15 SCP input * 3 14 Black adj. R Band gap 4 13 PLL auto 1 U4935B SECAM killer out GND Bell filter ref PLL ref 5 12 PLL auto 2 6 11 Black adj. B 7 10 - (B-Y) output 8 9611726 9 - (R-Y) output Figure 2. Connection diagram Absolute Maximum Ratings VS = 8 V, Tamb = 25C, reference point Pin 6, unless otherwise specified Test conditions: Vpin 1 = 4.75 V, Vpin 16 = 4 V, unless otherwise specified Parameters Supply voltage Junction temperature Storage temperature range Electrostatic handling*) Pin 3 Symbol VS Tj Tstg VESD Value 8.0 125 -40 to +125 Unit V C C V all Pins "200 *) Equivalent to discharging a 200 pF capacitor via a 0-W resistor Operating Range Parameters Supply voltage range Ambient temperature Pin 3 Symbol VS Tamb Value 7.5 to 8.5 -20 to +70 Unit V C Thermal Resistance Parameters Junction ambient (when soldered to PCB) Symbol RthJA Value 80 Unit K/W 2 (16) Preliminary Information TELEFUNKEN Semiconductors Rev. A1, 28-Jan-97 U4935B 1500 Power dissipation Pd ( mW ) 1250 1000 750 500 250 0 0 96 11702 25 50 75 100 125 150 Ambient temperature Tamb ( C ) Figure 3. Thermal derating curve of the package (maximum rating) Electrical Characteristics VS = 8 V, Tamb = 25C, reference point Pin 6, unless otherwise specified Test conditions: Vpin 1 = 4.75 V, Vpin 16 = 4 V, unless otherwise specified Parameters DC supply Supply voltage VS Supply current IS Bell filter Resonance frequency Test Conditions / Pins Pin 3 Pin 3 Note 1 f = 4.0 - 5.0 MHz sweep signal with 20 mV peak-to-peak amplitude at the CVBS input (see note 2, page 5), Pin 2 f = 4.0 - 5.0 MHz sweep signal with 20 mV peak-to-peak amplitude at the CVBS input, Pin 2 Pins 9 and 10 Black/ white signal at the CVBS input (see note 4, page 5), Pin 9 Black/ white signal at the CVBS input (see note 4, page 5), Pin 10 (see note 1, page 5), Pin 9 (see note 1, page 5), Pin 10 fBO 4.236 4.286 4.336 MHz Symbol VS IS Min. 7.5 18 Typ. 8.0 24 Max. 8.5 30 Unit V mA Bandwidth fBW 250 320 368 kHz Demodulator Output DC level during blanking Black level error -(R-Y) DVRB DVBB VR-Y VB-Y VO 2.1 -15 2.8 3.5 +15 V mV Black level error -(B-Y) -50 +20 mV -(R-Y) output signal amplitude (peak-to-peak value) -(B-Y) output signal amplitude (peak-to-peak value) 0.85 1.05 1.0 1.24 1.15 1.36 V V TELEFUNKEN Semiconductors Rev. A1, 28-Jan-97 3 (16) Preliminary Information U4935B Parameters Ratio of -(B-Y)/-(R-Y) output signal amplitude Linearity Test Conditions / Pins Symbol VB-Y/VB- Y Min. 1.10 Typ. 1.24 2.9 Max. 1.36 3.2 Unit (see notes 1 and 3, page 5) VLIN 2.6 Pin 10 Sandcastle pulse (see figures 16 and 17) Vertical blanking detection level Pin 15 VVB 1.0 Horizontal blanking detection level Pin 15 VHB 1.75 Burst-gate detection level Pin 15 VBG 3.5 Reference/ Identification Reference frequency During vertical blanking fref (see figure 4, 300 mVpp) Pin 1 System switches detection level Vext1 = variable VTH1 (at SECAM) (see figure 6), Pin 1 System switches detection level Vext1 = variable VTH2 1.5 (at no SECAM) (see figure 6), Pin 1 Sink current (at SECAM) (see note 5, page 5), Pin 1 125 Pin 5 voltage (at SECAM) (see note 1, page 5), Pin 5 V5S 2.4 Sensitivity of identification and Attenuate the amplitude I/K -46 killer (see notes 1 and 6, page 5) Pin 5 Unspecified characteristics (only for reference but not guaranteed limiting values) Input dynamic range Pin 16 VDR (peak-to-peak value) Chrominance input voltage (see note 7, page 5), Pin 16 VCL (peak-to-peak value) Pole frequency of the de-emphasis fp LPF Ratio of the pole and zero fp/fo frequency -(R-Y), -(B-Y) output impedance Pins 9 and 10 Zo1 (at SECAM) -(R-Y), -(B-Y) output impedance Pins 9 and 10 Zo2 1 (at no SECAM) Reference voltage amplitude (see note 8, page 5), Pin 1 Vref 0.2 (peak-to-peak value) Rising edge of SECAM burst-gate (see note 9, page 5) Tr pulse (internal generated) Falling edge of SECAM burst-gate (see note 10, page 5) Tf pulse 1.25 2.0 3.85 4.4336 1.4 2.25 4.2 V V V MHz 2.9 2.0 180 3.1 -38 3.3 V V 235 3.6 -32 mA V dB 1.0 167 85 3 200 1.4 300 V mV kHz 600 W MW V 0.57 4.5 0.2 ms ms 4 (16) Preliminary Information TELEFUNKEN Semiconductors Rev. A1, 28-Jan-97 U4935B Notes: 1. 2. 3. 4. CVBS input: 100/75 color bar signal. The (B-Y) burst signal [fOB] amplitude is 167 mVpp (= 0 dB). Measure during scanning. An active probe is recommended for low capacitive loading. Defined as VLIN = b / a (see figure 4). Measure the difference between the blanking (V1) and the black level (V2) (see figure 5). DVRB = V2 - V1 (Pin 9), DVBB = V2 - V1 (Pin 10) a V2 b V1 96 11720 96 11719 Figure 4. VLIN Figure 5. Black level error at Pin 9 (R-Y) 5. The external voltage at Pin 1 should exceed 0.5 V. 6. VK (peak-to-peak value of the burst signal in a blue line) when "LOW" (0.2 V) at Pin 5 related to 167 mVPP ( = 0 dB) I / K = 20 log10 (VK / 167 m V) [dB] 7. Measured in the burst period of a blue line 8. The reference frequency should be stable during the vertical blanking 9. Defined as the time from rising edge of the sandxastle burst-gate pulse at Pin 15. 10. Defined as the time from falling edge of the sandxastle burst-gate pulse at Pin 15. TELEFUNKEN Semiconductors Rev. A1, 28-Jan-97 5 (16) Preliminary Information U4935B Internal Pin Configuration 9611727 VCC 300 m A 4.3 V 2W 1 2.8 V 10 pF 2 kW 2 kW 18 k W 4.3 V 13 k W 15.1 k W 100 W 5 20 k W 96 11730 100 m A 7 Figure 6. fref / ident Figure 9. SECAM killer output 96 11733 VCC 100 W 2 20 k W 100 mA 96 11728 20 k W 100 mA Figure 7. Bell-filter output Figure 10. Bell-filter reference 8 VCC 2 kW 2 kW 4 1.8 k W 200 mA 9 kW 96 11729 12.6 k W Figure 11. PLL reference 96 11734 Figure 8. Band gap 6 (16) Preliminary Information TELEFUNKEN Semiconductors Rev. A1, 28-Jan-97 U4935B Internal Pin Configuration (continued) 96 11738 9, 10 230 50 m A 50 m A 50 m A mA 15 100W Figure 12. -(R-Y), -(B-Y) output Figure 15. Sandcastle input 96 11735 4 4.3 V 670 W 225 W 14 13 pF 16 2.5 k W 2.8 V 8.1 k W 1.11 kW 8.1 k W 200 m A 13.6 kW 11 96 11736 96 11739 200 m A 100m A Figure 13. Black level adjust -(B-Y), -(R-Y) channel 13 12 Figure 16. CVBS input 200 m A 200 m A 96 11737 Figure 14. PLL auto 1, 2 TELEFUNKEN Semiconductors Rev. A1, 28-Jan-97 7 (16) Preliminary Information U4935B Functional Description Bell Filter The ACC amplifier provides a C- (chrominance) signal of a constant peak-to-peak level for the bell filter. The bell filter is of a gyrator-capacitor type. The resonance frequency is 4.433619 MHz 4.286 MHz 4.33 MHz during vertical blanking during scanning during burst gating. The reference frequency should be stable during the vertical blanking because it is used to calibrate the filters and the demodulator. The capacitor C7 should be connected as close as possible to the ground Pin of the package. If not, this can result in a resonance frequency error. CVBS in ACC 16 VBLK pulse Bell filter fref/ ident Amp 1 7 C7 Tuning PLL Gain 9611724 fo 4.286 MHz fref 4.434 MHz f Figure 17. Block diagram of the bell filter 8 (16) Preliminary Information TELEFUNKEN Semiconductors Rev. A1, 28-Jan-97 U4935B Demodulator The bell filter delivers the C signal via a limiter amplifier to the demodulator. The demodulator is of a phase-locked loop (PLL) type VCO and a phase-emitter coupled multivibrator with the limiter output and is fed back to the VCO. The free-running frequency is adjusted by charging or discharging the capacitor at Pin 8 during the vertical blanking and is held during scanning. Therefore, the IC needs no adjustment to enable constant operation The low-frequency de-emphasis is matched to the PLL and is controlled by the tuning voltage of the PLL. The capacitor, C8, should be connected as close as possible to the ground pin of the package. If this is not ensured, a black-level error for both channels may result. VBLK pulse Bell-filter output De- emphasis to H, V blanking Limiter LPF VCO PLL Tuning 8 C8 9611721 PLL ref Figure 18. Block diagram of the demodulator TELEFUNKEN Semiconductors Rev. A1, 28-Jan-97 9 (16) Preliminary Information U4935B Identification The identification circuit is a quadrature-type FM demodulator which uses the bell filter as a phase shifter. The resonance frequency of the phase shifter is adjusted to 4.33 MHz i.e., the frequency between the 4.25-MHz (B-Y) carrier and the 4.40625-MHz (R-Y) carrier during burst gating. The output of the ACC is multiplied with the output of the phase shifter. The sample-and-hold circuit samples the output of the multiplier during burst gating and maintains this value outside of the burst-gate pulse time. The identification and killer detectors compare the sampled-and-hold voltage with internal detection levels. Only line identification (and no field identification) is implemented. * U4930B (PAL/NTSC decoder) to guarantee that the output signal from the decoder is available when no PAL signal has been identified. If a SECAM signal has been decoded, a request for "color on" is transmitted to Pin 1 (current sink: 180 mA). If the signal request is grated (i.e., Pin q is "HIGH" therefore no PAL), the output signals from the U4935B are switched on and the output pins of the U4930B have a high impedance. If no SECAM signal has been decoded, the outputs of the U4935B will be blanked or have high-impedance state depending on the logic level at Pin 1. (see table 1) SECAM Identification of the U4935B SECAM; 180 mA no SECAM; 0 mA SECAM; 180 mA no SECAM; 0 mA Output Pins 9, 10 of the U4935B (-R-Y), -(B-Y) signals Blanked High impedance * The identification circuit must communicate with the System Identification of the U4930B No PAL PAL Logic Level; Pin 1 of the U4935B HIGH (5.0 V) (5 0 LOW (1 5 V) (1.5 CVBS in ACC 16 VBLK BGP fH 2 Bell filter Bell-filter output S/H Identification detector output Killer detector output 9611722 Figure 19. Block diagram of the identification 10 (16) Preliminary Information TELEFUNKEN Semiconductors Rev. A1, 28-Jan-97 U4935B SECAM Switch, Output Stage The de-emphasis circuit provides the color-difference signals which are blanked during the horizontal and vertical blanking pulses. After blanking, the color difference signals are switched every (B-Y) and (R-Y) line by the SECAM switch. The (B-Y) signal is then amplified 3.8 times and available at Pin 10 after reversing. The (R-Y) signal is amplified 2.54 times and available at Pin 9. When the logic level at Pin 1 is "LOW", the outputs have high-impedance state. 3.85 V 2.0 V Pin 15 SCP in Pin 1 fref / ident 1.25 V BGP : 3.85 V HBLK : 2.0 V VBLK : 1.25 V fref = 4.433619 MHz 0.2 ~ 0.5 Vp-p 5.0 VDC at SECAM 1.5 VDC at no SECAM Pin 9 - (R-Y) out Pin 10 - (B-Y) out 96 11718 Figure 20. Timing waveforms of the output stage TELEFUNKEN Semiconductors Rev. A1, 28-Jan-97 11 (16) Preliminary Information U4935B Sandcastle Pulse The required blanking burst and fH/2 pulses are derived from a three-level sandcastle pulse. (see figures 16 and 17) 3.85 V 2.0 V 1.25 V Pin 15 SCP in HBLK F/F (fH/2 pulse) 125 ms VBLK SECAM sw SECAM sw 96 11716 Pin 15 SCP detection level : BGP : 3.85 V HBLK : 2.0 V VBLK : 1.25 V Figure 21. Timing chart of the internal pulses Pin 15 SCP in SECAM BGP 0.2 ms 4.5 ms 95 11717 Figure 22. Timing chart of the internal SECAM burst gating pulse 12 (16) Preliminary Information TELEFUNKEN Semiconductors Rev. A1, 28-Jan-97 U4935B Typical Voltages Pin 1 Function fref / ident DC Voltage Comment For the - reference input, - PAL system identification input, - SECAM killer-signal output. 180 mA typ. at SECAM 0 mA typ. at no SECAM System switches detection level = 2.9 V. 2 3 4 5 6 7 8 9 10 11 12 Bell-filter output Supply voltage Bell-filter ref. voltage output SECAM killer output Ground Bell-filter reference PLL reference -(R-Y) output -(B-Y) output Black level adjust B - channel PLL auto 2 1.7 V 8V 4.3 V 3.1 V 0V 3.3 V 4.3 V 2.8 V 2.8 V 4.16 V 5.0 V When SECAM When no SECAM 13 PLL auto 1 5.0 V 14 15 16 Black level adjust R - channel Sandcastle-pulse (SCP) input CVBS input 4.28 V The capacitor should be connected as close as possible to the ground pin of the package. 1.0 V (peak-to-peak value) when the color-bar signal at Pin 16 is 100/75. 1.24 V (peak-to-peak value) when the color-bar signal at Pin 16 is 100/75 Black-level error can be compensated by an external resistor Capacitor between Pin 12 and Pin 13 improves color S/N ratio. The value of the capacitor is typ. 0.1 mF. Capacitor between Pin 12 and Pin 13 improves color S/N ratio. The value of the capacitor is typ. 0.1 mF. Black-level error can be compensated by an external resistor 2.05 V TELEFUNKEN Semiconductors Rev. A1, 28-Jan-97 13 (16) Preliminary Information U4935B VS 10 mF A SCP input 5 kW 2 kW 0.1 m F RR RB Vext16 = 4 V 16 15 14 13 12 11 10 9 U4935B VS 150 pF fref 1 2 3 4 sw5 5 6 0.47 mF Vext5 =1.5 V 7 8 22 m F 0.1 m F 0.47 mF 5 kW Vext1 8.2 k W VS= 8 V 96 11725 Figure 23. Basic application circuit 14 (16) Preliminary Information TELEFUNKEN Semiconductors Rev. A1, 28-Jan-97 U4935B Package Information Package DIP16 Dimensions in mm 20.0 max 19.8 max 7.82 7.42 4.8 max 0.5 min 3.3 6.4 max 0.39 max 9.75 8.15 1.64 1.44 17.78 Alternative 16 15 14 13 0.58 0.48 2.54 12 11 10 9 technical drawings according to DIN specifications 96 11709 1 2 3 4 5 6 7 8 TELEFUNKEN Semiconductors Rev. A1, 28-Jan-97 15 (16) Preliminary Information U4935B Ozone Depleting Substances Policy Statement It is the policy of TEMIC TELEFUNKEN microelectronic GmbH to 1. Meet all present and future national and international statutory requirements. 2. Regularly and continuously improve the performance of our products, processes, distribution and operating systems with respect to their impact on the health and safety of our employees and the public, as well as their impact on the environment. It is particular concern to control or eliminate releases of those substances into the atmosphere which are known as ozone depleting substances ( ODSs). The Montreal Protocol ( 1987) and its London Amendments ( 1990) intend to severely restrict the use of ODSs and forbid their use within the next ten years. Various national and international initiatives are pressing for an earlier ban on these substances. TEMIC TELEFUNKEN microelectronic GmbH semiconductor division has been able to use its policy of continuous improvements to eliminate the use of ODSs listed in the following documents. 1. Annex A, B and list of transitional substances of the Montreal Protocol and the London Amendments respectively 2 . Class I and II ozone depleting substances in the Clean Air Act Amendments of 1990 by the Environmental Protection Agency ( EPA) in the USA 3. Council Decision 88/540/EEC and 91/690/EEC Annex A, B and C ( transitional substances ) respectively. TEMIC can certify that our semiconductors are not manufactured with ozone depleting substances and do not contain such substances. We reserve the right to make changes to improve technical design and may do so without further notice. Parameters can vary in different applications. All operating parameters must be validated for each customer application by the customer. Should the buyer use TEMIC products for any unintended or unauthorized application, the buyer shall indemnify TEMIC against all claims, costs, damages, and expenses, arising out of, directly or indirectly, any claim of personal damage, injury or death associated with such unintended or unauthorized use. TEMIC TELEFUNKEN microelectronic GmbH, P.O.B. 3535, D-74025 Heilbronn, Germany Telephone: 49 ( 0 ) 7131 67 2831, Fax number: 49 ( 0 ) 7131 67 2423 16 (16) Preliminary Information TELEFUNKEN Semiconductors Rev. A1, 28-Jan-97 |
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