VIDEO LOWPASS FILTERS SERIES ATLW Stopband Ratio @45dB = 1.32 ATCL Stopband Ratio @45dB = 1.14 ATBW Stopband Ratio @45dB = 1.08 ABW Stopband Ratio @42dB = 1.066 For many years amplitude, Delay and phase corrected filters have found applications in Television Broadcasting, Cable transmission, Direct Satellite Transmission, Analog and Digital Image Processing, Analog to Digital conversion and Computer Graphics. Allen Avionics offers four basic shape factors or stopband ratios in their range of Video Filters. ATLW General purpose filters include amplitude,Phase and Group Delay equalization to improve pulse and bar response. Smooth slower roll off reduces ringing. Can be used as in any Video bandwidth limiting application. Also used as anti aliasing pre filters in analog to digital conversion applications or as post aliasing filters with the addition of sin x/x correction. ATCL More complex filter for applications requiring a sharper cutoff rate. The tight control of amplitude, phase and delay of the ATCL series makes them ideal for high performance analog and digital applications. ATBW Almost a Brickwall Filter. The ATBW is a good compromise for sharpness, ringing, insertion loss and cost. The ATBW stopband ratio of 1.08 is close to the ABW series Brickwall ratio of 1.066 but has less ringing, Delay distortion and insertion loss. ABW A true Brickwall Filter. The ABW series is the sharpest cutoff Video filter available anywhere. Tight control of the Amplitude, Phase and Delay Characteristics create a filter unmatched for sharpness, low ringing, insertion loss and cost. Typical NTSC applications use this filter to pass 4.20MHz and reject everything above 4.48MHz which requires a stopband ratio of 1.066. See Brickwall data sheet. Basic ATLW Specifications ATLW PART Fp MHz NUMBER Ap < .2db ATLW0P46 0.46 ATLW0P93 0.93 ATLW1P40 1.40 ATLW1P87 1.87 ATLW2P34 2.34 ATLW2P57 2.57 ATLW2P80 2.80 ATLW2P92 2.92 ATLW3P27 3.27 ATLW3P74 3.74 ATLW3P97 3.97 ATLW4P03 4.03 ATLW4P21 4.21 ATLW4P68 4.68 ATLW4P91 4.91 ATLW5P15 5.15 ATLW5P43 5.43 ATLW5P61 5.61 ATLW6P08 6.08 ATLW6P55 6.55 ATLW7P02 7.02 ATLW7P49 7.49 ATLW7P95 7.95 ATLW8P42 8.42 ATLW8P89 8.89 ATLW9P36 9.36 F3dB Fs, MHz MHz As >45dB 0.52 0.61 1.03 1.22 1.55 1.85 2.06 2.47 2.58 3.09 2.84 3.40 3.09 3.70 3.22 3.86 3.61 4.32 4.12 4.94 4.38 5.25 4.44 5.32 4.64 5.56 5.15 6.18 5.41 6.48 5.67 6.80 5.98 7.17 6.19 7.40 6.70 8.03 7.22 8.65 7.73 9.27 8.25 9.89 8.76 10.50 9.28 11.12 9.79 11.74 10.31 12.36 Gd, ns FGd MHz Pd ns 220 110 75 55 45 40 37 36 32 28 26 25 25 25 21 20 19 18 17 16 15 14 13 12 12 12 0.44 0.89 1.33 1.78 2.22 2.45 2.67 2.77 3.11 3.56 3.78 3.83 4.00 4.45 4.67 4.90 5.16 5.34 5.79 6.23 6.68 7.12 7.57 8.01 8.46 8.90 5500 2750 1833 1375 1100 1000 917 881 786 688 647 638 611 550 524 500 474 458 423 393 367 344 324 306 289 275 PERFORMANCE Passband Flatness: Ripple Less than +/-.1dB Insertion Loss @ 100KHz =1.0dB Max Impedance =75 Ohms unbalanced Return Loss = -20dB typical Group Delay Ripple less than +/- 2% of midband delay Stopband Attenuation = 45dB Min Stopband Ratio = 1.32@-45dB Temperature Range Operating -20 to +65 Degrees Celsius KEY Fp Frequency at which amplitude ripple exceeds Ap (peak to peak ripple) Fs Frequency at which stopband attenuation exceeds As F3dB Nominal Frequency at which attenuation is 3dB Pd Nominal Propagation delay through filter in Nanoseconds Gd Typical passband group delay ripple, Nanoseconds peak-to-peak FGd Frequency at which group delay ripple limits is exceeded, MHz Ap Peak-to-peak passband ripple, dB As Minimum stopband attenuation, dB Basic ATCL Specifications ATCL PART Fp MHz Fs, NUMBER Ap < MHz As .2db >45dB ATCL0P46 0.46 0.53 ATCL0P93 0.93 1.06 ATCL1P40 1.40 1.60 ATCL1P87 1.87 2.13 ATCL2P34 2.34 2.66 ATCL2P57 2.57 2.92 ATCL2P80 2.80 3.19 ATCL2P92 2.92 3.32 ATCL3P27 3.27 3.72 ATCL3P74 3.74 4.26 ATCL3P97 3.97 4.52 ATCL4P03 4.03 4.59 ATCL4P21 4.21 4.80 ATCL4P68 4.68 5.34 ATCL4P91 4.91 5.59 ATCL5P15 5.15 5.87 ATCL5P43 5.43 6.19 ATCL5P61 5.61 6.39 ATCL6P08 6.08 6.94 ATCL6P55 6.55 7.47 ATCL7P02 7.02 8.00 ATCL7P49 7.49 8.54 ATCL7P95 7.95 9.07 ATCL8P42 8.42 9.60 ATCL8P89 8.89 10.13 ATCL9P36 9.36 10.67 Gd, ns FGd MHz Pd ns 265 134 89 67 53 49 45 43 38 33 32 31 30 27 25 24 23 22 21 19 18 17 16 15 14 13 0.43 0.86 1.30 1.73 2.17 2.39 2.60 2.71 3.04 3.48 3.69 3.75 3.91 4.35 4.57 4.79 5.05 5.22 5.65 6.09 6.52 6.96 7.40 7.83 8.26 8.70 8846 4466 2967 2233 1782 1619 1488 1428 1275 1114 1050 1035 990 890 849 810 768 743 686 637 594 557 524 495 468 445 PERFORMANCE Passband Flatness: Ripple Less than +/-.1dB Insertion Loss @ 100KHz =2.5dB Max Impedance =75 Ohms unbalanced Return Loss = -20dB typical Group Delay Ripple less than +/- 1.5% of midband delay Stopband Attenuation = 45dB Min Stopband Ratio = 1.14@-45dB Temperature Range Operating 0 to +50 Degrees Celsius Basic ATBW Specifications ATBW PART Fp MHz Fs, NUMBER Ap < MHz As .2db >45dB ATBW0P46 0.46 0.49 ATBW0P93 0.93 1.00 ATBW1P40 1.40 1.52 ATBW1P87 1.87 2.02 ATBW2P34 2.34 2.53 ATBW2P57 2.57 2.78 ATBW2P80 2.80 3.03 ATBW2P92 2.92 3.15 ATBW3P27 3.27 3.54 ATBW3P74 3.74 4.04 ATBW3P97 3.97 4.29 ATBW4P03 4.03 4.35 ATBW4P21 4.21 5.63 ATBW4P68 4.68 5.05 ATBW4P91 4.91 6.54 ATBW5P15 5.15 5.56 ATBW5P43 5.43 5.87 ATBW5P61 5.61 6.05 ATBW6P08 6.08 6.56 ATBW6P55 6.55 7.08 ATBW7P02 7.02 7.59 ATBW7P49 7.49 8.09 ATBW7P95 7.95 8.59 ATBW8P42 8.42 9.10 ATBW8P89 8.89 9.60 ATBW9P36 9.36 10.11 Gd, ns FGd MHz Pd ns 265 140 93 70 56 51 47 45 40 35 33 33 31 28 27 26 24 23 21 20 19 18 17 16 15 14 0.42 0.86 1.30 1.72 2.16 2.37 2.59 2.70 3.02 3.45 3.67 3.72 3.89 4.32 4.54 4.76 5.02 5.18 5.62 6.05 6.49 7.92 7.35 8.78 8.22 8.65 10612 5591 3710 2780 2222 2023 1857 1780 1590 1390 1310 1290 1235 1111 1059 1010 957 926 855 793 740 694 654 617 584 555 PERFORMANCE Passband Flatness: Ripple Less than +/-.1dB Insertion Loss @ 100KHz =4dB Max Impedance =75 Ohms unbalanced Return Loss = -20dB typical Group Delay Ripple less than +/- 1.25% of midband delay Stopband Attenuation = 45dB Min Stopband Ratio = 1.08@-45dB Temperature Range Operating 0 to +50 Degrees Celsius