FMS6143CSX

FMS6143 Low-Cost Three-Channel 4th-Order Standard Definition Video Filter Driver February 2007 FMS6143 Low-Cost Three-Channel 4th-Order Standard Definition Video Filter Driver Features ■ Three 4th-order 8MHz (SD) filters ■ Drives single, AC- or DC-coupled, video loads (2Vpp, 150Ω) ■ Drives dual, AC- or DC-coupled, video loads (2Vpp, 75Ω) ■ Transparent input clamping ■ AC- or DC-coupled inputs ■ AC- or DC-coupled outputs ■ DC-coupled outputs eliminate AC-coupling capacitors ■ 5V only ■ Robust 8kV ESD protection ■ Lead-free SOIC-8 package Description The FMS6143 Low-Cost Video Filter (LCVF) is intended to replace passive LC filters and drivers with a low-cost integrated device. Three 4th-order filters provide improved image quality compared to typical 2nd or 3rd-order passive solutions. The FMS6143 may be directly driven by a DC-coupled DAC output or an AC-coupled signal. Internal diode clamps and bias circuitry may be used if AC-coupled inputs are required (see Applications section for details). The outputs can drive AC- or DC-coupled single (150Ω) or dual (75Ω) loads. DC-coupling the outputs removes the need for output coupling capacitors. The input DC-levels are offset approximately +280mV at the output (see the Applications section for details). Applications ■ Cable set-top boxes ■ Satellite set-top boxes ■ DVD players ■ HDTV ■ Personal Video Recorders (PVR) ■ Video On Demand (VOD) Related Application Notes AN-8002 — FMS6418B 4:2:2 Application Note AN-6024 — FMS6xxx Product Series Understanding Analog Video Signal Clamps, Bias, DCRestore, and AC or DC Coupling Methods AN-6041 — PCB Layout Considerations for Video Filter / Drivers Functional Block Diagram IN1 Transparent Clamp 6dB OUT1 IN2 Transparent Clamp 6dB OUT2 IN3 Transparent Clamp 6dB OUT3 8MHz, 4th-order Figure 1. AC-Coupled Inputs and Outputs Ordering Information Part Number FMS6143CS FMS6143CSX © 2006 Fairchild Semiconductor Corporation FMS6143 Rev. 4.0.5 Package SOIC-8 SOIC-8 Pb-Free Yes Yes Operating Temperture Range -40°C to +85°C -40°C to +85°C Packaging Method Tube Tape and Reel www.fairchildsemi.com FMS6143 Low-Cost Three-Channel 4th-Order Standard Definition Video Filter Driver Pin Configuration IN1 IN2 IN3 1 2 3 4 8 OUT1 OUT2 OUT3 GND FMS6143 8-pin SOIC 7 6 5 VCC Figure 2. AC-Coupled Inputs and Outputs Pin Assignments Pin # 1 2 3 4 5 6 7 8 Name IN1 IN2 IN3 VCC GND OUT3 OUT2 OUT1 Type Input Input Input Input Output Output Output Output Video input, Channel 1 Video input, Channel 2 Video input, Channel 3 +5V supply, do not float Description Must be tied to ground, do not float Filtered output, Channel 3 Filtered output, Channel 2 Filtered output, Channel 1 © 2006 Fairchild Semiconductor Corporation FMS6143 Rev. 4.0.5 www.fairchildsemi.com 2 FMS6143 Low-Cost Three-Channel 4th-Order Standard Definition Video Filter Driver Absolute Maximum Ratings The “Absolute Maximum Ratings” are those values beyond which the safety of the device cannot be guaranteed. The device should not be operated at these limits. The parametric values defined in the Electrical Characteristics tables are not guaranteed at the absolute maximum ratings. The “Recommended Operating Conditions” table defines the conditions for actual device operation. Symbol VCC DC Supply Voltage Parameter Analog and Digital I/O Output Channel - Any One Channel (Do Not Exceed) Min. -0.3 -0.3 Max. 6.0 VCC + 0.3 50 Unit V V mA Note: 1. Functional operation under any of these conditions is NOT implied. Performance and reliability are guaranteed only if operating conditions are not exceeded. Reliability Information Symbols TJ TSTG TL θJA Parameter Junction Temperature Storage Temperature Range Lead Temperature (Soldering, 10s) Thermal Resistance, JEDEC Standard Multi-layer Test Boards, Still Air Min. -65 Typ. Max. 150 +150 300 Unit °C °C °C °C/W 115 Recommended Operating Conditions The Recommended Operating Conditions table defines the conditions for actual device operation. Recommended operating conditions are specified to ensure optimal performance to the datasheet specifications. Fairchild does not recommend exceeding them or designing to absolute maximum ratings. Symbols TA VCC VCC Range Parameter Operating Temperature Range Min. -40 +4.75 Typ. +5.00 Max. +85 +5.25 Unit °C V © 2006 Fairchild Semiconductor Corporation FMS6143 Rev. 4.0.5 www.fairchildsemi.com 3 FMS6143 Low-Cost Three-Channel 4th-Order Standard Definition Video Filter Driver DC Electrical Characteristics TA = 25°C, VCC = 5V, RSOURCE = 37.5Ω; all inputs are AC-coupled with 0.1μF; all outputs are AC-coupled with 220μF into 150Ω loads; unless otherwise noted. Symbol ICC VIN PSRR Parameter Supply Current (1) Conditions FMS6143 (No Load) Referenced to GND if DC-coupled DC (All Channels) Min. Typ. Max. Units 19 1.4 -50 27 mA Vpp dB Video Input Voltage Range Power Supply Rejection AC Electrical Characteristics TA = 25°C, VIN = 1Vpp, VCC = 5V, RSOURCE = 37.5Ω; all inputs are AC-coupled with 0.1μF; all outputs are AC-coupled with 220μF into 150Ω loads; unless otherwise noted. Symbol AV f1dB fc fSB DG DP THD XTALK SNR tpd Parameter Channel Gain(1) -1dB Bandwidth -3dB Bandwidth Attenuation (Stopband Reject) Differential Gain Differential Phase Output Distortion (All Channels) Crosstalk (Channel-to-Channel) Signal-to-Noise Ratio Propagation Delay (1) Conditions All Channels All Channels All Channels All Channels at f = 27MHz All Channels All Channels VOUT = 1.8Vpp, 1MHz at 1MHz All Channels, NTC-7 Weighting: 100kHz to 4.2MHz Delay from Input-to-Output, 4.5MHz Min. Typ. Max. Units 5.6 4.5 6.0 6.5 7.7 48 0.3 0.6 0.4 -60 75 59 6.6 dB MHz MHz dB % ° % dB dB ns Note: 1. 100% tested at 25°C. © 2006 Fairchild Semiconductor Corporation FMS6143 Rev. 4.0.5 www.fairchildsemi.com 4 FMS6143 Low-Cost Three-Channel 4th-Order Standard Definition Video Filter Driver Typical Performance Characteristics TA = 25°C, VCC = 5V, RSOURCE = 37.5Ω; all inputs AC-coupled with 0.1μF; all outputs are AC-coupled with 220μF into 150Ω loads; unless otherwise noted. 5 0 -5 -10 -15 -20 -25 -30 -35 -40 -45 -50 -60 2 1 30 20 10 1 Normalized Gain (dB) Delay (ns) 0 -10 -20 -30 -40 -50 -60 Mkr Frequency Ref 400kHz 1 2 3 6.53MHz 7.72MHz 27MHz Gain 6dB -1dB BW -3dB BW -47.13dB 3 1 = 8.2MHz (12.63ns) 400kHz 5 10 15 20 25 30 400kHz 5 10 15 20 25 30 Frequency (MHz) Frequency (MHz) Figure 3. Frequency Response -60 -70 -80 Figure 4. Group Delay vs. Frequency 0.2 NTSC Differential Gain (%) 0.1 0 -0.1 -0.2 -0.3 Noise (dB) -90 -100 -110 -120 -130 400kHz 1 2 3 4 5 6 Min = -0.20 Max = 0.13 ppMax = 0.33 1st 2nd 3rd 4th 5th 6th Frequency (MHz) Figure 5. Noise vs. Frequency Figure 6. Differential Gain 1.0 Differential Phase (deg) 0.8 0.6 0.4 0.2 0 -0.2 -0.4 NTSC Min = 0.00 Max = 0.59 ppMax = 0.59 1st 2nd 3rd 4th 5th 6th Figure 7. Differential Phase © 2006 Fairchild Semiconductor Corporation FMS6143 Rev. 4.0.5 www.fairchildsemi.com 5 FMS6143 Low-Cost Three-Channel 4th-Order Standard Definition Video Filter Driver Typical Application Diagrams The following circuit may be used for direct DC-coupled drive by DACs with an output voltage range of 0V to 1.4V. AC-coupled or DC-coupled outputs may be used with AC-coupled outputs, offering slightly lower power dissipation. DVD Player or STB 0.1 μF 1.0 μF +5V 1 ROUT 2 IN1 OUT1 8 75Ω 220μF 75Ω Video Cables R 75Ω 7 GOUT IN2 OUT2 75Ω 220μF G 75Ω Video SoC BOUT 3 IN3 FMS6143 8L SOIC OUT3 6 75Ω 220μF B 75Ω 4 VCC GND 5 DAC Load Resistors per SoC specs AC-Coupling Caps are Optional Figure 8. Typical Application Diagram © 2006 Fairchild Semiconductor Corporation FMS6143 Rev. 4.0.5 www.fairchildsemi.com 6 FMS6143 Low-Cost Three-Channel 4th-Order Standard Definition Video Filter Driver Application Information Application Circuits The FMS6143 Low Cost Video Filter (LCVF) provides 6dB gain from input to output. In addition, the input is slightly offset to optimize the output driver performance. The offset is held to the minimum required value to decrease the standing DC current into the load. Typical voltage levels are shown in the diagram below: 1.0 -> 1.02V 0.65 -> 0.67V 0.3 -> 0.32V 0.0 -> 0.02V VIN 0.65V YIN 75Ω Video Cables LOAD2 (optional) 75Ω Driver LOAD1 YOUT 75Ω Video Cables 75Ω Figure 10. Input Clamp Circuit I/O Configurations For a DC-coupled DAC drive with DC-coupled outputs, use this configuration: 0V - 1.4V 2.28V 1.58V 0.88V 0.28V VOUT Driven by: DC-Coupled DAC Outputs AC-Coupled and Clamped Y, CV, R, G, B DVD or STB SoC DAC Output LCVF Clamp Inactive 75Ω There is a 280mV offset from the DC input level to the DC output level. VOUT = 2 * VIN + 280mV. Figure 11. DC-Coupled Inputs and Outputs 0.85V 0.5V 0.15V VIN 1.98V 1.28V 0.58V VOUT 0V - 1.4V Alternatively, if the DAC’s average DC output level causes the signal to exceed the range of 0V to 1.4V, it can be AC coupled as follows: Driven by: AC-Coupled and Biased U, V, Pb, Pr, C DVD or STB SoC DAC Output 0.1μ LCVF Clamp Active 75Ω Figure 9. Typical Voltage Levels The FMS6143 provides an internal diode clamp to support AC-coupled input signals. If the input signal does not go below ground, the input clamp does not operate. This allows DAC outputs to directly drive the FMS6143 without an AC coupling capacitor. When the input is AC-coupled, the diode clamp sets the sync tip (or lowest voltage) just below ground. The worst-case sync tip compression due to the clamp can not exceed 7mV. The input level set by the clamp, combined with the internal DC offset, keeps the output within its acceptable range. For symmetric signals like Chroma, U, V, Pb, and Pr, the average DC bias is fairly constant and the inputs can be AC-coupled with the addition of a pull-up resistor to set the DC input voltage. DAC outputs can also drive these same signals without the AC coupling capacitor. A conceptual illustration of the input clamp circuit is shown in Figure 10: Figure 12. AC-Coupled Inputs, DC-Coupled Outputs When the FMS6143 is driven by an unknown external source or a SCART switch with its own clamping circuitry, the inputs should be AC coupled like this: 0V - 1.4V 0.1μ External video source must be AC coupled 75Ω LCVF Clamp Active 75Ω Figure 13. SCART with DC-Coupled Outputs © 2006 Fairchild Semiconductor Corporation FMS6143 Rev. 4.0.5 www.fairchildsemi.com 7 FMS6143 Low-Cost Three-Channel 4th-Order Standard Definition Video Filter Driver The same method can be used for biased signals, with the addition of a pull-up resistor to make sure the clamp never operates. The internal pull-down resistance is 800kΩ ±20%, so the external resistance should be 7.5MΩ to set the DC level to 500mV: External video source must be AC coupled External video source must be AC coupled 0V - 1.4V 0.1μ LCVF Clamp Active 75Ω 220μ 75Ω 7.5MΩ 0.1μ LCVF Bias Input 75Ω Figure 17. Biased SCART with AC-Coupled Outputs NOTE: The video tilt or line time distortion is dominated by the AC-coupling capacitor. The value may need to be increased beyond 220μF to obtain satisfactory operation in some applications. 75Ω 500mV +/-350mV Figure 14. Biased SCART with DC-Coupled Outputs The same circuits can be used with AC-coupled outputs if desired. 0V - 1.4V 0.1μ 220μ Power Dissipation The FMS6143 output drive configuration must be considered when calculating overall power dissipation. Care must be taken not to exceed the maximum die junction temperature. The following example can be used to calculate the power dissipation and internal temperature rise. Tj = TA + Pd • θJA where: Pd = PCH1 + PCH2 + PCH3 and PCHx = VCC • ICH - (VO /RL) 2 DVD or STB SoC DAC Output LCVF Clamp Active 75Ω EQ. 1 EQ. 2 EQ. 3 EQ. 4 EQ. 5 where: VO = 2VIN + 0.280V ICH = (ICC/3) + (VO/RL) VIN = RMS value of input signal Figure 15. DC-Coupled Inputs, AC-Coupled Outputs 0V - 1.4V ICC = 19mA VCC = 5V RL = channel load resistance Board layout can also affect thermal characteristics. Refer to the Layout Considerations section for details. The FMS6143 is specified to operate with output currents typically less than 50mA, more than sufficient for a dual (75Ω) video load. Internal amplifiers are current limited to a maximum of 100mA and should withstand brief-duration short-circuit conditions. This capability is not guaranteed. DVD or STB SoC DAC Output 0.1μ LCVF Clamp Active 75Ω 220μ Figure 16. AC-Coupled Inputs and Outputs © 2006 Fairchild Semiconductor Corporation FMS6143 Rev. 4.0.5 www.fairchildsemi.com 8 FMS6143 Low-Cost Three-Channel 4th-Order Standard Definition Video Filter Driver Layout Considerations General layout and supply bypassing play a major role in high-frequency performance and thermal characteristics. Fairchild offers a demonstration board to guide layout and aid device evaluation. The demo board is a four-layer board with full power and ground planes. Following this layout configuration provides optimum performance and thermal characteristics for the device. For the best results, follow the steps and recommended routing rules listed below. Thermal Considerations Since the interior of most systems, such as set-top boxes, TVs, and DVD players, are at +70ºC; consideration must be given to providing an adequate heat sink for the device package for maximum heat dissipation. When designing a system board, determine how much power each device dissipates. Ensure that devices of high power are not placed in the same location, such as directly above (top plane) or below (bottom plane), each other on the PCB. Recommended Routing/Layout Rules ■ Do not run analog and digital signals in parallel. ■ Use separate analog and digital power planes to supply PCB Thermal Layout Considerations ■ Understand the system power requirements and environmental conditions. ■ Maximize thermal performance of the PCB. ■ Consider using 70μm of copper for high-power designs. ■ Make the PCB as thin as possible by reducing FR4 power. ■ Traces should run on top of the ground plane at all times. ■ No trace should run over ground/power splits. ■ Avoid routing at 90-degree angles. ■ Minimize clock and video data trace length differences. ■ Include 10μF and 0.1μF ceramic power supply bypass thickness. ■ Use vias in power pad to tie adjacent layers together. ■ Remember that baseline temperature is a function of capacitors. ■ Place the 0.1μF capacitor within 0.1 inches of the device board area, not copper thickness. ■ Modeling techniques provide a first-order approximation. power pin. ■ Place the 10μF capacitor within 0.75 inches of the device power pin. ■ For multi-layer boards, use a large ground plane to help dissipate heat. ■ For two-layer boards, use a ground plane that extends beyond the device body at least 0.5 inches on all sides. Include a metal paddle under the device on the top layer. ■ Minimize all trace lengths to reduce series inductance. © 2006 Fairchild Semiconductor Corporation FMS6143 Rev. 4.0.5 www.fairchildsemi.com 9 FMS6143 Low-Cost Three-Channel 4th-Order Standard Definition Video Filter Driver Mechanical Dimensions Dimensions are in millimeters unless otherwise noted. Figure 18. SOIC-8 Package © 2006 Fairchild Semiconductor Corporation FMS6143 Rev. 4.0.5 www.fairchildsemi.com 10 FMS6143 Low-Cost Three-Channel 4th-Order Standard Definition Video Filter Driver © 2006 Fairchild Semiconductor Corporation FMS6143 Rev. 4.0.5 www.fairchildsemi.com 11