(MAX7450 - MAX7452) Video-Signal Conditioners

www.DataSheet4U.com 19-3267; Rev 2; 11/04 Video-Signal Conditioners with AGC and Back-Porch Clamp General Description The MAX7450/MAX7451/MAX7452 complete front-end video-signal conditioners are designed to improve the quality of standard-definition video signals. The devices restore the DC level of the video input, correct for amplitude errors up to ±6dB, detect fault conditions, and filter out-of-band noise. The MAX7450/MAX7451/ MAX7452 optimize the signal quality for further video processing through a crosspoint switch or video decoder (ADC). Each device integrates an input video clamp, automatic gain control (AGC), loss-of-sync (LOS) detector, and an out-of-band noise/lowpass filter. These devices also incorporate a user-selectable buffer gain (0 or +6dB) and an AGC-disable function. The MAX7450 and MAX7451 operate from dual power supplies of ±5V or ±3.3V respectively, and they restore the video blanking level to GND. The MAX7452 operates from a single +5V supply and features a user-adjustable clamp level. The devices are available in an 8-pin SO package with an exposed pad and are specified for operation over the extended (-40°C to +85°C) temperature range. Features ♦ Back-Porch Clamp to GND (MAX7450/MAX7451) ♦ Adjustable Back-Porch Clamp (MAX7452) ♦ Automatic Gain Control (±6dB Range) Normalizes Signals to Standard Video Level ♦ Input Fault Detection with LOS Output ♦ Inherent 50Hz/60Hz Input Rejection of 60dB ♦ Single-Supply Operation: MAX7452 (+5V) ♦ Out-of-Band Noise Filter ♦ Output Buffer Drives Standard 150Ω Video Load with 0dB or +6dB Gain ♦ Dual-Supply Operation MAX7450 (±5V) MAX7451 (±3.3V) ♦ Tiny 8-Pin SO Package MAX7450/MAX7451/MAX7452 Ordering Information PART† MAX7450ESA MAX7451ESA MAX7452ESA TEMP RANGE PINSUPPLY PACKAGE VOLTAGE (V) ±5 ±3.3 Applications Signal Conditioner for Standard-Definition Video Inputs Security Video Systems Video-Switching Systems -40°C to +85°C 8 SO-EP* -40°C to +85°C 8 SO-EP* -40°C to +85°C 8 SO-EP* +5 *EP = Exposed pad. †Package code = S8E-12. Functional Diagram VCC GAIN SET (0dB OR +6dB) VIDEO INPUT IN NOISE FILTER ±6dB 0 OR +6dB OUT 75Ω 75Ω SYNC SEPARATOR AND AMPLITUDE DETECTOR LOS AGCD MAX7450 MAX7451 VSS GND ________________________________________________________________ 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. Video-Signal Conditioners with AGC and Back-Porch Clamp MAX7450/MAX7451/MAX7452 ABSOLUTE MAXIMUM RATINGS VCC to GND MAX7450/MAX7452...........................................................+6V MAX7451 ...........................................................................+4V VSS to GND MAX7450.............................................................................-6V MAX7451.............................................................................-4V OUT MAX7450/MAX7451 ..........................................-2.5V to +3.5V MAX7452 ................................................-0.3V to (VCC + 0.3V) GSET, AGCD, LOS .....................................-0.3V to (VCC + 0.3V) All Other Pins MAX7450/MAX7451...................(-0.3V + VSS) to (VCC + 0.3V) MAX7452 ................................................-0.3V to (VCC + 0.3V) Maximum Current into Any Pin ............……………………±50mA Continuous Power Dissipation (TA = +70°C) 8-Pin SO (derate 18.9mW/°C above +70°C)..............1509mW 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 (VSUPPLY = ±5V ±5% (MAX7450), VSUPPLY = ±3.3V ±5% (MAX7451), VSUPPLY = +5V ±5% (MAX7452), RL=150Ω to GND, CL = 0 to 20pF, GSET = 1, AGCD = 1, TA = TMIN to TMAX, unless otherwise noted. Typical values are at TA = +25°C.) PARAMETER Clamp Accuracy Back-Porch Level Input Range Clamp Response Time VBPLVL tCLAMP SYMBOL CONDITIONS MAX7450/MAX7451, relative to GND MAX7452, relative VBPLVL = 1.5V MAX7452 GSET = 0 GSET = 1 1.5 1.2 70 ±10 % ±10 -6.0 -0.3 10 f = 100kHz ∆tG dG dθ GSET = 0 GSET = 1 0.95 1.85 1 2 0.2 0.2 1.05 2.05 15 0.6 0.6 +6.0 +0.3 dB dB MHz V/V ns % Degrees MIN TYP MAX ±50 ±50 2.4 2.0 UNITS mV V Lines Blanking level at the output to 1% of final value GSET = 0, relative to VOUT = 1VP-P GSET = 1, relative to VOUT = 2VP-P AGC Accuracy AGCD = 0, VIN = 0.5VP-P to 2VP-P AGC Input Range Gain Flatness Noise-Filter Cutoff Low-Frequency Gain Group-Delay Deviation Differential Gain Differential Phase GF Fc AGCD = 0, relative to VIN = 1VP-P f = 5MHz relative to 100kHz 3.58/4.43MHz relative to 100kHz Five-step modulated staircase (VIN = 1VP-P) Five-step modulated staircase (VIN = 1VP-P) 2 _______________________________________________________________________________________ Video-Signal Conditioners with AGC and Back-Porch Clamp ELECTRICAL CHARACTERISTICS (continued) (VSUPPLY = ±5V ±5% (MAX7450), VSUPPLY = ±3.3V ±5% (MAX7451), VSUPPLY = +5V ±5% (MAX7452), RL=150Ω to GND, CL = 0 to 20pF, GSET = 1, AGCD = 1, TA = TMIN to TMAX, unless otherwise noted. Typical values are at TA = +25°C.) PARAMETER SYMBOL CONDITIONS Output signal peak-to-peak to RMS noise (100Hz to 5MHz) 18µs, 100 IRE bar 130 lines, 18µs, 100IRE bar 1 VIN = 1VP-P, dG / dP < 3% / degrees AGCD = 1 Power-Supply Rejection Ratio PSRR VCC + 100mVP-P, f = 3.5MHz MAX7450 Supply Current MAX7451 MAX7452 Logic-High Input Logic-Low Input Logic-High Output Logic-Low Output Input Current Logic-High Input Current Logic-Low VIH VIL VOH VOL IIH IIL ISOURCE = 500µA ISINK = 500µA Logic input sink Logic input source VCC 0.5 0.4 10 10 0.7 x VCC 0.3 x VCC AGCD = 0 with maximum gain 2 30 20 35 30 20 V V V V µA µA mA dB GSET = 0, VOUT = 1VP-P GSET = 1, VOUT = 2VP-P MIN 68 dB 65 0.2 0.5 5 2.4 % % µA VP-P TYP MAX UNITS MAX7450/MAX7451/MAX7452 Signal-to-Noise Ratio SNR Line Time Distortion Field Time Distortion Input Leakage Current Output Dynamic Range HDIST VDIST IIN _______________________________________________________________________________________ 3 Video-Signal Conditioners with AGC and Back-Porch Clamp MAX7450/MAX7451/MAX7452 Typical Operating Characteristics VSUPPLY = ±5V ±5% (MAX7450), VSUPPLY = ±3.3V ±5% (MAX7451), VSUPPLY = +5V ±5% (MAX7452), RL= 150Ω to GND, CL = 0 to 20pF, GSET = 1, AGCD = 1. TA = +25°C, unless otherwise noted. GROUP DELAY vs. FREQUENCY MAX7450 toc01 2T RESPONSE DIFFERENTIAL PHASE (DEGREES) DIFFERENTIAL GAIN (%) MAX7450 toc02 DIFFERENTIAL GAIN 0.2 0 -0.2 -0.4 1st 0.3 0.2 0.1 0 -0.1 -0.2 -0.3 1st 2nd 3rd 4th 5th 6th 2nd 3rd 4th 5th 6th MAX7450 toc03 60 0.4 50 GROUP DELAY (ns) 40 IN 200mV/div 30 DIFFERENTIAL PHASE 20 OUT 200mV/div 0.1 1 FREQUENCY (MHz) 10 t = 200ns/div 10 PASSBAND AMPLITUDE vs. FREQUENCY MAX7450 toc04 AMPLITUDE vs. FREQUENCY 0 GAIN = 2V / V -10 AMPLITUDE (dB) -20 -30 -40 -50 -60 -70 GAIN = 1V / V MAX7450 toc05 8 6 4 AMPLITUDE (dB) 2 0 -2 -4 -6 -8 -10 0.1 1 FREQUENCY (MHz) GAIN = 1V / V GAIN = 2V / V 10 10 0.1 1 10 100 FREQUENCY (MHz) SUPPLY CURRENT vs. TEMPERATURE MAX7450 toc06 BACK-PORCH VOLTAGE vs. TEMPERATURE MAX7450 BACK-PORCH VOLTAGE (mV) -1 -2 -3 -4 -5 -6 MAX7450 toc07 35 MAX7450 33 SUPPLY CURRENT (mA) 0 31 29 27 25 -40 -15 10 35 60 85 TEMPERATURE (°C) -40 -15 10 35 60 85 TEMPERATURE (°C) 4 _______________________________________________________________________________________ Video-Signal Conditioners with AGC and Back-Porch Clamp MAX7450/MAX7451/MAX7452 Typical Operating Characteristics (continued) VSUPPLY = ±5V ±5% (MAX7450), VSUPPLY = ±3.3V ±5% (MAX7451), VSUPPLY = +5V ±5% (MAX7452), RL= 150Ω to GND, CL = 0 to 20pF, GSET = 1, AGCD = 1. TA = +25°C, unless otherwise noted. OUTPUT BACK-PORCH LEVEL (MAX7450) MAX7450 toc08 AGC RESPONSE ENVELOPE (VIN = 0.5VP-P) MAX7450 toc09 AGC RESPONSE ENVELOPE (VIN = 2VP-P) MAX7450 toc10 AGCD = 0 VOUT = 2VP-P IN AC-COUPLED 200mV/div 500mV/div OUT 200mV/div BACK-PORCH = 0V AGCD = 0 VOUT = 2VP-P 500mV/div 1µs 400ms/div 400ms/div Pin Description PIN MAX7450/ MAX7451 1 2 3 4 — 5 6 7 8 — MAX7452 1 2 3 — 4 5 6 7 8 — NAME FUNCTION Positive Power Supply. Connect +5V to VCC for the MAX7450/MAX7452. Connect +3.3V to VCC for the MAX7451. Bypass to GND with 1µF and 0.1µF capacitors as close to the pin as possible. Video Input. AC-couple video signal through a 0.1µF capacitor. Ground Negative Power Supply. Connect -5V to VSS for the MAX7450. Connect -3.3V to VSS for the MAX7451. Bypass to GND with 1µF and 0.1µF capacitors as close to the pin as possible. Back-Porch Level Input. When gain = 2V/V (GSET = 1), output back-porch level is equal to BPLVL input. When gain = 1V/V (GSET = 0), output back-porch level is equal to VBPLVL/1.5. Automatic Gain-Control Disable Input. Disable AGC by driving AGCD to VCC. Enable AGC by driving AGCD to GND. Video Output Gain-Setting Input. Drive GSET high to set buffer gain to +6dB. Drive GSET low to set buffer gain to 0dB. Loss-of-Sync Logic Output. LOS is high when video sync is lost for more than 15 horizontal lines. LOS goes low when video sync is present. Exposed Pad. Connect to VSS (MAX7450/MAX7451). Connect to GND (MAX7452). VCC IN GND VSS BPLVL AGCD OUT GSET LOS EP _______________________________________________________________________________________