19-2989; Rev 0; 10/03 KIT ATION EVALU LE B A IL A AV 4-Channel RGB Video Filter with Asynchronous CVBS Input The MAX7448 processes RGB and asynchronous CVBS video signals. The output video buffers have a fixed gain of +6dB. The channel used for CVBS video has high-frequency boost circuitry, which provides picture sharpness with +1.2dB of gain boost without degradation in the stopband. The output video drivers can be disabled with an external pin. The MAX7448 is available in a 14-pin TSSOP package with an exposed pad, and is specified over the -40°C to +85°C extended temperature range. Features ♦ 4-Channel Filter and Buffer for RGB and CVBS Video Signals ♦ Filter Response Ideal for NTSC, PAL, and Interlaced SDTV Video Signals ♦ 43dB (typ) Stopband Attenuation at 27MHz ♦ ±0.75dB (max) Passband Ripple Out to 5MHz ♦ Blanking Level Voltage on Cable <1V ♦ Each Channel Drives Two 150Ω Video Loads ♦ +5V Single-Supply Voltage ♦ Small 14-Pin TSSOP Package Ordering Information PART MAX7448EUD TEMP RANGE PIN-PACKAGE -40°C to +85°C 14 TSSOP-EP* *EP = Exposed pad. Applications Set-Top Boxes/HDRs Game Consoles DVD Players Digital VCRs Pin Configuration appears at end of data sheet. Desktop Video Editors Functional Diagram VCC ENCODER 75Ω 0.1µF G D/A (WITH SYNC) 75Ω * INA LOWPASS FILTER OUTA SYNC DETECTOR 75Ω * 75Ω 0.1µF R D/A LOWPASS FILTER OUTB LOWPASS FILTER OUTC LOWPASS FILTER OUTD 75Ω 75Ω INC 75Ω 75Ω 0.1µF CVBS D/A (WITH SYNC) 75Ω * INB 0.1µF B D/A 75Ω IND SYNC DETECTOR 75Ω * * * * * 75Ω 75Ω 75Ω 75Ω 75Ω *OPTIONAL CAPACITORS MAX7448 GND DISABLE ________________________________________________________________ Maxim Integrated Products For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at 1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com. 1 MAX7448 General Description The MAX7448, 4-channel, buffered video reconstruction filter is ideal for anti-aliasing and digital-to-analog converter (DAC)-smoothing video applications or wherever analog video is reconstructed from a digital data stream (such as cable/satellite/terrestrial set-top boxes, DVD players, hard-disk recorders (HDRs), and personal video recorders (PVRs)). This device operates from a single +5V supply and has a flat passband out to 5MHz with a stopband attenuation of 43dB at 27MHz. This makes it ideal for use with NTSC, PAL, and standarddefinition digital TV (SDTV) video systems. Each output is capable of driving two standard 150Ω video loads. MAX7448 4-Channel RGB Video Filter with Asynchronous CVBS Input ABSOLUTE MAXIMUM RATINGS VCC to GND ...........................................................................+6V All Other Pins to GND.................................-0.3V to (VCC + 0.3V) Maximum Current into Any Pin Except VCC and GND .....±50mA Continuous Power Dissipation (TA = +70°C) TSSOP-EP (derate 20.8mW/°C above +70°C) ...........1667mW Operating Temperature Range ...........................-40°C to +85°C Storage Temperature Range .............................-65°C to +150°C Junction Temperature ......................................................+150°C Lead Temperature (soldering, 10s) .................................+300°C Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability. ELECTRICAL CHARACTERISTICS (VCC = +5V ±5%, CL = 0 to 20pF, RL = 75Ω to GND for DC-coupled load, RL = 75Ω to VCC / 2 for AC-coupled load, CIN_ = 0.1µF, GAIN = +6dB,TA = TMIN to TMAX, unless otherwise noted. Typical values are at VCC = +5V, TA = +25°C.) PARAMETER SYMBOL CONDITIONS f = 100kHz to 5MHz, relative to 100kHz Passband Response MIN TYP MAX Channels A, B, C +0.75 +0.15 +0.75 Channel D +0.9 +1.2 +1.5 39 43 UNITS dB Stopband Attenuation ASB f ≥ 27MHz Differential Gain dG 5-step modulated staircase 0.15 0.50 % Differential Phase dθ 5-step modulated staircase 0.15 0.50 Degrees Signal-to-Noise Ratio Group Delay Deviation Line-Time Distortion SNR ∆tg Peak signal (2VP-P) to RMS noise, f = 100Hz to 50MHz Deviation from 100kHz to 4.1MHz dB 80 dB Channels A, B, C 11 20 Channel D 17 30 HDIST 18µs, 100 IRE bar Field-Time Distortion VDIST 130 lines, 18µs, 100 IRE bar 0.5 % Clamp Settling Time tCLAMP To ±1% 100 Lines Output DC Clamp Level Channels A, D 0.6 0.9 1.1 Channels B, C 1.1 1.5 1.8 f = 100kHz -3 Low-Frequency Gain Accuracy AV Low-Frequency Gain Matching AV(MATCH) Low-frequency channel-to-channel matching, f = 100kHz Group Delay Matching tg(MATCH) Low-frequency channel-to-channel matching, f = 100kHz Channel-to-Channel Crosstalk XTALK Output Short-Circuit Current ISC Input Leakage Current IIN Input Dynamic Swing 0.3 ns % V +3 % 4 % 2 ns f = 100kHz to 3.58MHz 60 dB OUT_ shorted to GND or VCC 70 mA 10 Channels A, D 1.2 Channels B, C 0.9 µA VP-P SUPPLY Supply Voltage Range Supply Current Power-Supply Rejection Ratio 2 VCC ICC PSRR 4.75 No load 100 VIN = 100mVP-P, f = 0 to 3.5MHz 40 _______________________________________________________________________________________ 5.25 V 140 mA dB 4-Channel RGB Video Filter with Asynchronous CVBS Input (VCC = +5V ±5%, CL = 0 to 20pF, RL = 75Ω to GND for DC-coupled load, RL = 75Ω to VCC / 2 for AC-coupled load, CIN_ = 0.1µF, GAIN = +6dB, TA = TMIN to TMAX, unless otherwise noted. Typical values are at VCC = +5V, TA = +25°C.) PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS DISABLE Output Impedance during Disable Disable Logic-Input High Voltage Disable Logic-Input Low Voltage Disable Logic-Input Current ZDISABLE At 5MHz 2 VIH kΩ 2.0 V VIL IDISABLE VIL = 0V (sink), VIH = VCC (source) 0.8 V ±10 µA Typical Operating Characteristics (VCC = +5V, TA = +25°C, unless otherwise noted.) PASSBAND AMPLITUDE vs. FREQUENCY 0 1.5 HIGH-FREQUENCY BOOST PHASE RESPONSE vs. FREQUENCY 200 150 100 -40 PHASE (DEGREES) AMPLITUDE (dB) AMPLITUDE (dB) 1.0 -20 0.5 0 -0.5 FLAT PASSBAND RESPONSE -1.5 NORMALIZED TO 0dB 0 -50 -150 NORMALIZED TO 0dB -80 -200 -2.0 1 50 -100 -1.0 -60 MAX7448 toc03 MAX7448 toc01 2.0 MAX7448 toc02 AMPLITUDE vs. FREQUENCY 10 FREQUENCY (MHz) 100 0.1 1 FREQUENCY (MHz) 10 0.1 1 10 FREQUENCY (MHz) _______________________________________________________________________________________ 3 MAX7448 ELECTRICAL CHARACTERISTICS (continued) Typical Operating Characteristics (continued) (VCC = +5V, TA = +25°C, unless otherwise noted.) GROUP DELAY vs. FREQUENCY MAX7448 toc06 MAX7448 toc05 MAX7448 toc04 90 GROUP DELAY (ns) MODULATED 12.5T RESPONSE (1 IRE = 7.14mV) 2T RESPONSE (1 IRE = 7.14mV) 100 80 IN_ IN_ 250mV/div 250mV/div OUT_ OUT_ 250mV/div 250mV/div 70 60 50 0.1 200ns/div 400ns/div DIFFERENTIAL GAIN MULTIBURST RESPONSE 10 1 FREQUENCY (MHz) 110 100 90 80 -40 -15 10 35 TEMPERATURE (°C) 4 60 85 MAX7448 toc09 0.3 0.2 0.1 0 -0.1 -0.2 -0.3 MAX7448 toc08 MAX7448 toc07 INPUTS BIASED TO +2V NO LOAD DIFFERENTIAL PHASE (DEGREES) DIFFERENTIAL GAIN (%) SUPPLY CURRENT vs. TEMPERATURE 120 SUPPLY CURRENT (mA) MAX7448 4-Channel RGB Video Filter with Asynchronous CVBS Input IN_ 250mV/div 1st 2nd 3rd 4th 5th 6th DIFFERENTIAL PHASE 0.3 0.2 0.1 0 -0.1 -0.2 -0.3 OUT_ 250mV/div 1st 2nd 3rd 4th 5th 6th _______________________________________________________________________________________ 10µs/div 4-Channel RGB Video Filter with Asynchronous CVBS Input PIN NAME FUNCTION 1 INA Channel A Video Input. Use channel A for the green (G with sync) video signal. AC-couple INA with a series 0.1µF capacitor. 2 INB Channel B Video Input. Use channel B for the red (R) video signal. AC-couple INB with a series 0.1µF capacitor. 3 INC Channel C Video Input. Use channel C for the blue (B) video signal. AC-couple INC with a series 0.1µF capacitor. 4 IND Channel D Video Input. Use channel D for a CVBS (with sync) signal. AC-couple IND with a series 0.1µF capacitor. 5 DISABLE 6–9 GND Ground 10 VCC +5V Supply Input 11 OUTD Channel D Buffer Output. This output can be either AC- or DC-coupled. 12 OUTC Channel C Buffer Output. This output can be either AC- or DC-coupled. Disable Logic Input. A logic-low on DISABLE enables the output buffers. A logic-high on DISABLE disables all buffer outputs and puts them in a high-impedance state. Detailed Description Filter The MAX7448 filters and buffers video-encoder DAC outputs in applications such as set-top boxes, HDRs, DVD players, and digital VCRs. The MAX7448 reconstructs and cleans up analog video signals from the output of DAC video encoders. Each channel consists of a lowpass filter and an output video buffer that can drive two standard 150Ω video loads. Filter Response The reconstruction filter consists of two 2nd-order SallenKey stages. The Butterworth-type response features a maximally flat passband for NTSC and PAL bandwidths. The stopband offers at least 43dB (typ) of attenuation at a video-encoder DAC sampling frequency of 27MHz (see the Typical Operating Characteristics). The MAX7448 is designed to process R, G (with sync), B, and CVBS ASYNC video signals. The video signal processed by channel A (G video signal) requires a sync pulse. This sync pulse provides the required timing for channels A, B, and C. Channel D allows an asynchronous video signal to be processed with its own local sync separator. This device operates from a single +5V supply and has a nominal cutoff frequency of 5MHz optimized for NTSC, PAL, and SDTV. High-Frequency Boost The +1.2dB high-frequency boost on channel D (CVBS video signal) increases image sharpness by compensating for signal degradation and rolloff in the video encoder. Channels A, B, and C do not boost high-frequency signals and have a flat response over the video bandwidth. Output Buffers Each output buffer has a fixed gain of +6dB and can drive two 150Ω video loads with a 2VP-P signal. The MAX7448 can drive an AC load or drive the video load directly without using a large output capacitor. The output buffers drive DC loads with an output blanking level of less than 1V. _______________________________________________________________________________________ 5 MAX7448 Pin Description MAX7448 4-Channel RGB Video Filter with Asynchronous CVBS Input Output Clamp Level Power-Supply Bypassing and Layout When a sync pulse is detected on channel A, the DC restore loop is activated for channel A, B, and C. Channel D’s DC restore loop is activated by the sync pulse on channel D. The function of the loop is to set the DC level of the video signal to the specified level of the signal type (R, G, B, CVBS). See Table 1 for clamp levels and sync sources. The MAX7448 operates from a single +5V supply. Bypass VCC to GND with a 0.1µF capacitor. Place all external components as close to the device as possible. Table 1. Output Clamp Level and Sync Source CHANNEL CLAMP LEVEL (V) SYNC SOURCE A 0.9 Channel A B 1.5 Channel A C 1.5 Channel A D 0.9 Channel D Applications Information Input Considerations Use 0.1µF ceramic capacitors to AC-couple the inputs. These input capacitors store a DC level so the outputs are clamped to an appropriate DC voltage level. Exposed Pads The TSSOP-EP package has an exposed pad on the bottom of the package. This pad is electrically connected to GND and should be connected to the ground plane for improved thermal conductivity. Do not route signals under this package. Pin Configuration TOP VIEW INA 1 14 OUTA INB 2 13 OUTB INC 3 12 OUTC IND 4 MAX7448 DISABLE 5 11 OUTD 10 VCC GND 6 9 GND GND 7 8 GND TSSOP Output Considerations The outputs are typically connected to a 75Ω series back-match resistor followed by the video cable. Because of the inherent divide-by-two of this configuration, the voltage on the video cable is always less than 1V, complying with industry-standard video requirements such as the European SCART standard (which allows up to 2V of DC on the video cable). The video buffer can also drive an AC-coupled video load. Good video performance is achieved with an output capacitor as low as 220µF. 6 Chip Information TRANSISTOR COUNT: 6300 PROCESS: BiCMOS _______________________________________________________________________________________ 4-Channel RGB Video Filter with Asynchronous CVBS Input TSSOP 4.4mm BODY.EPS PACKAGE OUTLINE, TSSOP, 4.40 MM BODY EXPOSED PAD 21-0108 C 1 1 Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are implied. Maxim reserves the right to change the circuitry and specifications without notice at any time. Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 _____________________ 7 © 2003 Maxim Integrated Products Printed USA is a registered trademark of Maxim Integrated Products. MAX7448 Package Information (The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information, go to www.maxim-ic.com/packages.)