Video Switch

www.DataSheet4U.com 19-3560; Rev 0; 1/05 Video Switch for Dual SCART Connectors General Description The MAX7457 4-channel video switch is ideal for antialiasing and DAC-smoothing video applications or wherever analog video is reconstructed from a digital data stream such as cable/satellite/terrestrial set-top boxes (STBs), DVD players, hard disk recorders (HDRs), and personal video recorders (PVRs). The MAX7457 filters and buffers CVBS and RGB video signals, making it ideal for dual SCART (peritelevision) STBs with an auxiliary CVBS input. The MAX7457 operates from a single +5V supply and has a flat passband out to 5MHz with a stopband attenuation of 43dB at 27MHz, making it ideal for NTSC, PAL, and standard-definition digital TV (SDTV) video systems. The MAX7457 output buffers have a fixed gain of +6dB and are capable of driving two standard 150Ω video loads. The channel for CVBS video has high-frequency boost circuitry that enhances picture sharpness with up to +1.2dB of gain boost without degradation in the stopband. The video output drivers can be disabled by an external control input. The MAX7457 is available in a 16-pin, 5mm x 5mm x 0.8mm TQFN package, and is specified over the extended (-40°C to +85°C) temperature range. Features ♦ 4-Channel Video Filter/Buffer for RGB and CVBS Signals with Auxiliary Input ♦ Allows Auxiliary Input for CVBS Video LoopThrough Applications ♦ 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 Operation ♦ Available in 5mm x 5mm x 0.8mm, 16-Pin TQFN MAX7457 Ordering Information PART MAX7457ETE TEMP RANGE -40°C to +85°C PIN-PACKAGE 16 TQFN-EP* PKG CODE T1655-2 Applications STBs/HDRs Game Consoles Desktop Video Editors DVD Players Digital VCRs *EP = Exposed pad. Pin Configuration appears at end of data sheet. Typical Operating Circuit VCC SELA 0.1µF INA2 0.1µF 2-TO-1 MUX LOWPASS FILTER SYNC DETECTOR +6dB OUTA 75Ω * 75Ω 75Ω * 75Ω AUXILIARY VIDEO SOURCE (VCR, DVD, ETC.) ENCODER CVBS D/A INA1 75Ω 0.1µF R D/A INB LOWPASS FILTER +6dB OUTB 75Ω * 75Ω * 75Ω 75Ω 0.1µF G D/A INC LOWPASS FILTER +6dB OUTC 75Ω * 75Ω * 75Ω 75Ω 0.1µF B D/A IND LOWPASS FILTER +6dB OUTD 75Ω * 75Ω * 75Ω MAX7457 GND DISABLE *OPTIONAL CAPACITORS ________________________________________________________________ Maxim Integrated Products 1 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. www.DataSheet4U.com Video Switch for Dual SCART Connectors MAX7457 ABSOLUTE MAXIMUM RATINGS VCC to GND ..............................................................-0.3V to +6V INA1, INA2, INB, INC, IND to GND ............-0.3V to (VCC + 0.3V) OUTA, OUTB, OUTC, OUTD to GND .........-0.3V to (VCC + 0.3V) SELA, DISABLE to GND .............................-0.3V to (VCC + 0.3V) Maximum Current into Any Pin Except VCC and GND .....±50mA Continuous Power Dissipation (TA = +70°C) 16-Pin TQFN (derate 20.8mW/°C above +70°C)..........................................................1666.7mW 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, TA = TMIN to TMAX, unless otherwise noted. Typical values are at VCC = 5V, TA = +25°C.) PARAMETER Passband Flatness Stopband Attenuation Differential Gain Differential Phase Signal-to-Noise Ratio ASB dG dθ SNR SYMBOL CONDITIONS Channel INA_ f = 100kHz to 5MHz, relative to 100kHz f ≥ 27MHz 5-step modulated staircase 5-step modulated staircase Peak signal (2VP-P) to RMS noise, f = 100Hz to 50MHz Channel INA_ Group Delay Deviation Line-Time Distortion Field-Time Distortion Clamp Settling Time Output DC Clamp Level Low-Frequency Gain Accuracy Low-Frequency Gain Matching Group Delay Matching Channel-to-Channel Crosstalk Disabled Output Impedance Output Short-Circuit Current AV AV(MATCH) tg(MATCH) XTALK ZDISABLE ISC ∆tg HDIST VDIST tCLAMP Deviation from 100kHz to 4.1MHz 18µs, 100 IRE bar 130 lines, 18µs, 100 IRE bar To ±1% Channel INA_ Channel INB, INC, IND f = 100kHz, relative to gain of +6dB Low-frequency channel-to-channel matching, f = 100kHz Low-frequency channel-to-channel matching, f = 100kHz f = 100kHz to 3.58MHz At 5MHz OUT_ shorted to GND or VCC 2 -60 2 70 0.6 1.1 -3 300 0.9 1.5 1.1 1.8 +3 4 Channels INB, INC, IND Channels INB, INC, IND MIN +0.9 -0.75 40 TYP +1.2 +0.15 43 0.15 0.15 80 17 11 30 20 0.3 0.5 ns % % Lines V % % ns dB kΩ mA 0.5 0.5 MAX +1.5 +0.75 dB dB % Degrees dB UNITS 2 _______________________________________________________________________________________ www.DataSheet4U.com Video Switch for Dual SCART Connectors ELECTRICAL CHARACTERISTICS (continued) (VCC = +5V ±5%, CL = 0 to 20pF, RL = 75Ω to GND for DC-coupled load, RL = 75Ω to VCC/2 for AC-coupled load, TA = TMIN to TMAX, unless otherwise noted. Typical values are at VCC = 5V, TA = +25°C.) PARAMETER Input Leakage Current Input Dynamic Swing Mux Crosstalk SUPPLY Supply Voltage Range Supply Current Power-Supply Rejection Ratio LOGIC INTERFACE Logic Input High Voltage Logic Input Low Voltage Logic Input Current VIH VIL VIL = 0 (sink), VIH = VCC (source) 2.0 0.8 ±10 V V µA VCC ICC PSRR No load VIN = 100mVP-P, f = 0 to 3.5MHz 4.75 100 40 5.25 140 V mA dB SYMBOL IIN Channel INA_ Channels INB, INC, IND f = 100kHz to 4.1MHz -60 CONDITIONS MIN TYP MAX 10 1.2 0.9 UNITS µA VP-P dB MAX7457 Typical Operating Characteristics (VCC = +5V, TA = +25°C, unless otherwise noted.) AMPLITUDE vs. FREQUENCY MAX7457 toc01 PASSBAND AMPLITUDE vs. FREQUENCY 1.5 1.0 CHANNEL INA_ MAX7457 toc02 PHASE RESPONSE vs. FREQUENCY 150 100 PHASE (DEGREES) 50 0 -50 -100 -150 -200 MAX7457 toc03 2.0 200 0 AMPLITUDE (dB) AMPLITUDE (dB) -20 0.5 0 -0.5 CHANNELS INB/INC/IND -1.0 -40 -60 CHANNEL INA_ -80 1 10 FREQUENCY (MHz) 100 -1.5 -2.0 0.1 1 FREQUENCY (MHz) 10 0.1 1 FREQUENCY (MHz) 10 _______________________________________________________________________________________ 3 www.DataSheet4U.com Video Switch for Dual SCART Connectors MAX7457 Typical Operating Characteristics (continued) (VCC = +5V, TA = +25°C, unless otherwise noted.) GROUP DELAY vs. FREQUENCY MAX7457 toc04 2T RESPONSE (1 IRE = 7.14mV) MAX7457 toc05 MODULATED 12.5T RESPONSE (1 IRE = 7.14mV) MAX7457 toc06 100 90 GROUP DELAY (ns) 80 70 60 50 40 0.1 1 FREQUENCY (MHz) IN_ 300mV/div IN_ 300mV/div OUT_ 300mV/div OUT_ 300mV/div 10 200ns/div 400µs/div DIFFERENTIAL GAIN (%) SUPPLY CURRENT vs. TEMPERATURE MAX7457 toc07 DIFFERENTIAL GAIN 0.3 0.2 0.1 0 -0.1 -0.2 -0.3 1 0.3 0.2 0.1 0 -0.1 -0.2 -0.3 1 2 3 4 5 6 7 2 3 4 5 6 7 MAX7457 toc08 MULTIBURST RESPONSE MAX7457 toc09 120 INPUTS BIASED TO +2V NO LOAD SUPPLY CURRENT (mA) 110 IN_ 250mV/div 100 DIFFERENTIAL PHASE (DEGREES) DIFFERENTIAL PHASE OUT_ 250mV/div 90 80 -40 -15 10 35 60 85 TEMPERATURE (°C) 10µs/div 4 _______________________________________________________________________________________ www.DataSheet4U.com Video Switch for Dual SCART Connectors Pin Description PIN 1 2 3 4 5 6, 8, 14 7 9 10 11 12 13 15 16 — NAME INB INC IND DISABLE SELA N.C. GND VCC OUTD OUTC OUTB OUTA INA2 INA1 EP FUNCTION Channel INB Video Input. Use channel INB for the red (R) signal. AC-couple INB with a series 0.1µF capacitor. Channel INC Video Input. Use channel INC for the green (G) signal. AC-couple INC with a series 0.1µF capacitor. Channel IND Video Input. Use channel IND for the blue (B) signal. AC-couple IND with a series 0.1µF capacitor. 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. Select A Input. A logic low on SELA selects INA1 and a logic high on SELA selects INA2. No Connection. Not internally connected. Ground +5V Supply Input Channel D Video Output. OUTD can be either AC- or DC-coupled. Channel C Video Output. OUTC can be either AC- or DC-coupled. Channel B Video Output. OUTB can be either AC- or DC-coupled. Channel A Video Output. OUTA can be either AC- or DC-coupled. Channel INA2 Video Input. Connect auxiliary CVBS to INA2. AC-couple INA2 with a series 0.1µF capacitor. Channel INA1 Video Input. Connect CVBS to INA1. AC-couple INA1 with a series 0.1µF capacitor. Exposed Pad. Connect to GND for improved thermal heat sinking. MAX7457 Detailed Description The MAX7457 4-channel video switch filters and buffers video encoder DAC outputs in applications such as STBs, HDRs, DVD players, and digital VCRs. The MAX7457 offers an auxiliary CVBS loop-through feature required in dual SCART applications. Audio and video switching in SCART STBs utilize a costly integrated A/V switch offering high-end features such as volume control and high audio-drive capability. A more cost-effective solution uses the MAX7457 for the video switching along with low-cost standard passive analog switches for the audio switching. The MAX7457 reconstructs and cleans up analog video signals from the video encoder’s DAC output. Each ch