www.fairchildsemi.com ML6415 S-Video Filter with Summed Composite Output, Sound Trap, and Group Delay Compensation Features General Description • • • • • The ML6415 is a dual Y/C 4th-order Butterworth lowpass video filter optimized for minimum overshoot and flat group delay. The device also contains a summing circuit to generate filtered composite video, an audio trap and group delay compensation circuit to notch-out audio, providing an area for the addition of the FM audio carrier(s) and mimic the group delay distortion introduced at the transmitter. The group delay predistortion compensates for the nominal TV receiver IF filter distortion. • • • • • • 7.1MHz Y and C filters, with CV out 14dB notch at 4.5MHz for sound trap 42dB stopband attenuation at 27MHz on Y, C, and CV Better than 1dB flatness to 4.5 MHz on Y, C, and CV RF Modulator output differential group delay between 400kHz and 3.58MHz is typically -170ns. No external frequency select components or clocks 9ns group delay flatness on Y, C, and CV output AC coupled inputs and outputs 0.4% differential gain on Y, C and CV channels, 0.4º differential phase on Y, C and CV channels 0.8% total harmonic distortion on all channels DC restore with low tilt Applications • Cable Set-top Boxes • Satellite Set-top Boxes • DVD Players In a typical application, the Y and C input signals from DACs are AC coupled into the filter. Both channels have DC restore circuitry to clamp the DC input levels during video sync. The Y and C channels use a separate feedback clamp. The clamp pulse is derived from the Y channel. The outputs are AC coupled. The Y, C, CV, and modulator outputs can drive 2Vpp into a 150Ω load (1Vpp 75Ω coax load). The Y, C, CV, and notch channels have a gain of approximately 2 (6dB) with 1Vpp input levels. Block Diagram VCC 7 SYNC STRIP, REFERENCE, AND TIMING YIN 1 4TH – ORDER FILTER ×2 gM 8 YOUT 6 CVOUT 2 RF MOD 5 COUT + 1V Σ ×2 + gM CIN 4 1V 4TH – ORDER FILTER NOTCH, GROUP DELAY ×2 3 GND REV. 2F May 2003 ML6415 DATA SHEET Pin Configuration ML6415 8-Pin SOIC (S08) YIN 1 8 YOUT RF MOD 2 7 VCC GND 3 6 CVOUT CIN 4 5 COUT TOP VIEW Pin Descriptions Pin # Signal Name Description 1 YIN 2 RF MOD 3 GND Ground 4 CIN Chrominance input 5 COUT 6 CVOUT 7 VCC 5V supply 8 YOUT Luminance output Luminance input Output to RF modulator driver Chrominance output Composite video output Functional Description Introduction This product is a dual monolithic continuous time video filter designed for reconstructing the luminance and chrominance signals from an S-Video D/A source. Composite video output is generated by summing the Y and C outputs. The chip is intended for use in applications with AC coupled input and AC coupled outputs. (See Figure 1) The reconstruction filters approximate a 4th-order Butterworth characteristic with an optimization toward low overshoot and flat group delay. Y, C, and CV outputs are capable of driving 2Vpp into AC coupled 150Ω video loads, with up to 35pF of load capacitance at the output pin. All channels are clamped during sync to establish the appropriate output voltage swing range. Thus the input coupling capacitors do not behave according to the conventional RC time constant. Clamping for all channels settles to less than 10mv within 5ms of a change in video input sources. In most applications the input coupling capacitors are 0.1µF. The Y and C input typically sinks 1µA during active video, 2 which nominally tilts a horizontal line by about 2mV at the Y output. During sync, the clamp typically sources 20µA to restore the DC level. The net result is that the average input current is zero. Any change in the input coupling capacitor’s value will inversely alter the amount of tilt per line. Such a change will also linearly affect the clamp response times. This product is robust and stable under all stated load and input conditions. Capacitive bypassing VCC directly to ground ensures this performance. Luminance (Y) I/O The luma input is driven by either a low impedance source of 1VP-P or the output of a 75Ω terminated line. The input is required to be AC coupled via a 0.1µF coupling capacitor which allows for a settling time of 5ms. The luma output is capable of driving an AC coupled 150Ω load at 2Vpp, or 1Vpp into a 75Ω load. Up to 35pF of load capacitance (at the output pin) can be driven without stability or slew issues. The output is AC coupled with a 400µF or larger AC coupling capacitor. REV. 2F May 2003 DATA SHEET ML6415 Chrominance (C) I/O Composite Video (CV) Output The chroma input is driven by a low impedance source of 0.7Vpp or the output of a 75Ω terminated line. The input is required to be AC coupled via a 0.1µF coupling capacitor which allows for a clamp setting time of 5ms. The chroma output is capable of driving an AC coupled 150Ω load at 2VP-P, or 1VP-P into a 75Ω load. Up to 35pF of load capacitance can be driven without stability or slew issues. A 0.1µF AC coupling capacitor is recommended at the output. (This reduces the circuit cost as chroma does not contain low frequency components.) The composite video output is capable of driving 2 loads to 2VP-P. It is intended to drive a TV and a VCR. Either the TV input or the VCR input can be shorted to ground and the other output will still meet specifications. Up to 35pF of load capacitance (at the output pin) can be driven without stability or slew issues. RF Modulator Output The RF modulator output is capable of driving a 600Ω load to 2VP-P, but is primarily intended to drive a modulator load. Typical Applications Diagram 4.5MHz FM SOUND + NOTCH AND GROUP DELAY PROTECTION 2 0.1µF 1 YIN Σ VIDEO MODULATOR 220µF 75Ω 8 4th-ORDER FILTER VIDEO CABLES YOUT 75Ω + ENCODER TO CHANNEL 3 OR 4 6 Σ 220µF 75Ω CVOUT TO TV 75Ω + 220µF 0.1µF CIN 4 5 4th-ORDER FILTER CVOUT TO VCR 75Ω 220µF 7 75Ω 75Ω COUT 3 75Ω 5.0V 0.1µF 1µF Figure 1. Coupled S-Video, Composite Video Line Driver, Sound Trap, and Group Delay Pre-distortion REV. 2F May 2003 3 ML6415 DATA SHEET Absolute Maximum Ratings Absolute maximum ratings are those values beyond which the device could be permanently damaged. Absolute maximum ratings are stress ratings only and functional device operation is not implied. Parameter Min. Max. Units DC Supply Voltage –0.3 7 V Analog & Digital I/O GND – 0.3 VCC + 0.3 V Output Current (Continuous) CV Channel C and Y Channels 60 30 mA mA Junction Temperature 150 °C 150 °C Lead Temperature (Soldering, 10s) 260 °C Thermal Resistance (θJA) 115 °C/W Min. Max. Units 0 70 °C 4.5 5.5 V Storage Temperature Range –65 Operating Conditions Parameter Temperature Range VCC Range Electrical Characteristics Unless otherwise specified, VCC = 5.0V ±10%, All inputs AC coupled with 100nF, TA = Operating Temperature Range Symbol Parameter Conditions ICC Supply Current VCC Supply Range AVYC Low Frequency Gain (YOUT, COUT) at 400KHz 60 85 mA 4.5 5.0 5.5 V 5.75 6.0 6.25 dB at 400KHz 6.1 6.7 7.3 dB Low Frequency Gain (CVOUT) at 400KHz 5.55 5.9 6.25 dB COUT Output Level (During Sync) Sync Present on YIN 1.6 2.0 2.4 V YOUT Output Level (During Sync) Sync Present on YIN 0.75 1.0 1.25 V CVOUT Output Level (During Sync) Sync Present on YIN 0.75 1.0 1.25 V RFMOD Output Level (During Sync) Sync Present on YIN 0.65 1.0 1.35 V AVRFMOD Low Frequency Gain (RFMOD) AVCV tCLAMP Clamp Response Time (Y Channel) Settled to Within 10mV, 0.1µF cap on YIN and CIN f1dB –1.0dB Bandwidth (Flatness) (YOUT, COUT, and CVOUT) fC –3dB Bandwidth (Flatness) (YOUT, COUT, and CVOUT) fSB Stopband Rejection (YOUT, COUT, and CVOUT) fIN = 27MHz to 100MHz worst case Vi Input Signal Dynamic Range (All Channels) AC Coupled ISC Output Short Circuit Current (All Channels) COUT, YOUT, CVOUT, or RFMOD to GND (Note 1) 4 Min. Typ. Max. Units 5 ms 4.5 MHz 7.1 MHz -37 –42 dB 1.2 1.4 Vpp 4.0 40 80 mA REV. 2F May 2003 DATA SHEET ML6415 Electrical Characteristics (continued) Unless otherwise specified, VCC = 5.0V ±10%, All inputs AC coupled with 100nF, TA = Operating Temperature Range Symbol Parameter Conditions Min. Typ. Max. Units CL Output Shunt Capacitance (All Channels) All Outputs 35 pF dG Differential Gain YOUT, COUT, and CVOUT 0.4 % dP Differential Phase YOUT, COUT, and CVOUT 0.4 ° THD Output Distortion (All Channels) VOUT = 1.8Vpp, Y/C Out at 3.58MHz 0.8 % XTALK Crosstalk From CIN of 0.5Vpp at 3.58MHz to YOUT –55 dB From YIN of 0.4Vpp at 3.58MHz, to COUT –58 dB PSRR PSRR (All Channels) 0.5Vpp (100kHz) at VCC –40 dB SNR Y, C Channel NTC-7 weighting 4.2MHz lowpass -75 dB CV Channel NTC-7 weighting 4.2MHz lowpass -69 dB RFMOD Channel NTC-7 weighting 4.2MHz lowpass -60 dB 70 ns tpd Group Delay (Y, C, CV) ∆tpd Group Delay Deviation from Flatness (Y, C, and CV) to 3.58MHz (NTSC) 9 ns tSKEW Skew Between YOUT and COUT at 1MHz 0 ns Tpd Group Delay RFMOD f = 3.58MHz (referenced to 400kHz) -230 -170 -130 ns Tpass Pass Delay, RFMOD Output f = 200kHz to 3MHz ns -50 50 dGRFMOD Differential Gain RFMOD Channel 1.5 % dPRFMOD Differential Phase RFMOD Channel 1.0 ° pK Gain Peaking (Note 2) RFMOD Channel at 2.0MHz MCF Modulator Channel Flatness (Note 2) at 3.75MHz AV Notch Attenuation (Note 2) From 4.425MHz to 4.63MHz AV Notch Attenuation (Note 2) at 4.2MHz PSRRmt Supply Sensitivity Modulator Channel Flatness VCC = 4.5V to 5.5V at 3.58MHz 0.12 dB/V TCm Modulator Channel Flatness Temperature Sensitivity VCC = 5V at 3.58MHz -0.04 dB/°C -0.5 0.5 -0.5 0.75 dB +0.75 dB 14 dB 8 dB Notes 1. Sustained short circuit protection limited to 10 seconds 2. Referenced to 400kHz 3. Group delay is tested down to 400kHz but guaranteed by design to 200kHz. REV. 2F May 2003 5 ML6415 DATA SHEET Mechanical Dimensions inches/(millimeters) Package: S08 8-Pin SOIC 0.189 - 0.199 (4.80 - 5.06) 8 0.148 - 0.158 0.228 - 0.244 (3.76 - 4.01) (5.79 - 6.20) PIN 1 ID 1 0.017 - 0.027 (0.43 - 0.69) (4 PLACES) 0.050 BSC (1.27 BSC) 0.059 - 0.069 (1.49 - 1.75) 0° - 8° 0.055 - 0.061 (1.40 - 1.55) 0.012 - 0.020 (0.30 - 0.51) 0.004 - 0.010 (0.10 - 0.26) 0.015 - 0.035 (0.38 - 0.89) 0.006 - 0.010 (0.15 - 0.26) SEATING PLANE 6 REV. 2F May 2003 ML6415 DATA SHEET Ordering Information Part Number Temperature Range Package ML6415CS 0° to 70° 8 Pin SOIC (S08) DISCLAIMER FAIRCHILD SEMICONDUCTOR RESERVES THE RIGHT TO MAKE CHANGES WITHOUT FURTHER NOTICE TO ANY PRODUCTS HEREIN TO IMPROVE RELIABILITY, FUNCTION OR DESIGN. FAIRCHILD DOES NOT ASSUME ANY LIABILITY ARISING OUT OF THE APPLICATION OR USE OF ANY PRODUCT OR CIRCUIT DESCRIBED HEREIN; NEITHER DOES IT CONVEY ANY LICENSE UNDER ITS PATENT RIGHTS, NOR THE RIGHTS OF OTHERS. LIFE SUPPORT POLICY FAIRCHILD’S PRODUCTS ARE NOT AUTHORIZED FOR USE AS CRITICAL COMPONENTS IN LIFE SUPPORT DEVICES OR SYSTEMS WITHOUT THE EXPRESS WRITTEN APPROVAL OF THE PRESIDENT OF FAIRCHILD SEMICONDUCTOR CORPORATION. As used herein: 1. Life support devices or systems are devices or systems which, (a) are intended for surgical implant into the body, or (b) support or sustain life, and (c) whose failure to perform when properly used in accordance with instructions for use provided in the labeling, can be reasonably expected to result in a significant injury of the user. www.fairchildsemi.com 2. A critical component in any component of a life support device or system whose failure to perform can be reasonably expected to cause the failure of the life support device or system, or to affect its safety or effectiveness. 2003 Fairchild Semiconductor Corporation