Document 282-1 Diplex Filters For DOCSIS 1.0, 1.1, 2.0 These diplex filter modules provide both low pass and high pass filtering in low cost units that meet the requirements of the DOCSIS 1.0, 1.1 and 2.0 standards.They are intended for two-way broadcast applications like cable modems, set-top boxes and HFC cable network equipment. The DPX-C parts are low-profile surface mount units that require a minimum of board space. The DPX-B are shielded and come with an integrated coaxial F connector. In addition to the designs shown here, Coilcraft can custom-engineer diplexers for specific applications. For free evaluation samples, contact Coilcraft or order them on-line at www.coilcraft.com. Low pass filter Insertion Passband loss Part number DOCSIS standard DPX4254-B DPX4254-C 1.0 1.0 5 – 42 MHz 5 – 42 MHz DPX4288-B DPX4288-C 1.1, 2.0 1.1, 2.0 5 – 42 MHz 5 – 42 MHz Return loss High pass filter Insertion Passband loss ≤1.0 dB ≤1.5 dB ≥15 dB ≥15 dB 54 – 860 MHz 54 – 860 MHz ≤1.5 dB ≤1.5 dB ≥10 dB ≥10 dB 88 – 860 MHz 88 – 860 MHz Return loss Irms1 (mA) ≤1.5 dB ≤1.5 dB ≥15 dB ≥15 dB 500 150 ≤1.5 dB ≤1.5 dB ≥10 dB ≥10 dB 500 150 1. Average current for a 15°C temperature rise above 25°C ambient. 2. Operating temperature range –40°C to +85°C. 3. Electrical specifications at 25°C. Schematic – Shielded Filters (-B) Diplex filter Schematic – Surface Mount Filters (-C) 1 High pass filter 2 4 1 F connector F connector (1) Low pass filter 3 5 2 High pass Diplex filter 3 Low pass 4, 5 Impedance: 75 ohms all ports Low pass (3) Ground (5) High pass (2) Ground (4) Impedance: 75 ohms all ports Specifications subject to change without notice. Please check our website for latest information. © Coilcraft, Inc. 2007 Document 282-1 Revised 01/11/08 Document 282-2 Shielded Diplex Filter – DPX4254-B High pass response 0 0 20 20 40 40 S21 S31 Low pass response 60 60 80 80 100 100 1 10 100 1000 1 Frequency (MHz) 100 1000 Frequency (MHz) Return loss Isolation 0 0 10 20 20 40 S32 S11 10 30 60 40 80 50 100 1 10 100 1000 1 Frequency (MHz) 10 100 1000 Frequency (MHz) Unshielded Diplex Filter – DPX4254-C High pass response 0 0 20 20 40 40 S21 S31 Low pass response 60 60 80 80 100 100 1 10 100 1000 1 Frequency (MHz) 100 1000 Frequency (MHz) Return loss Isolation 0 0 10 20 20 40 S32 S11 10 30 60 40 80 50 100 1 10 100 1000 1 Frequency (MHz) 100 1000 Frequency (MHz) Specifications subject to change without notice. Please check our website for latest information. © Coilcraft, Inc. 2007 10 Document 282-2 Revised 01/11/08 Document 282-3 Shielded Diplex Filter – DPX4288-B High pass response 0 0 20 20 40 40 S21 S31 Low pass response 60 60 80 80 100 100 1 10 100 1000 1 Frequency (MHz) 100 1000 Frequency (MHz) Return loss Isolation 0 0 10 20 20 40 S32 S11 10 30 60 40 80 50 100 1 10 100 1000 1 Frequency (MHz) 10 100 1000 Frequency (MHz) Unshielded Diplex Filter – DPX4288-C High pass response 0 0 20 20 40 40 S21 S31 Low pass response 60 60 80 80 100 100 1 10 100 1000 1 Frequency (MHz) 100 1000 Frequency (MHz) Return loss Isolation 0 0 10 20 20 40 S32 S11 10 30 60 40 80 50 100 1 10 100 1000 1 Frequency (MHz) 100 1000 Frequency (MHz) Specifications subject to change without notice. Please check our website for latest information. © Coilcraft, Inc. 2007 10 Document 282-3 Revised 01/11/08 Document 282-4 Dimensions – DPX4254-B, DPX4288-B Dimensions – DPX4254-C A A C B D E B F F G G I 3 1 2 5 K L J 4 D 3/8 - 32 UNEF 2A F connector H H Recommended Land Pattern Packaged 32 per tray C A B C D max max max typ E F G H I J K L 1.065 0.560 0.215 0.155 0.050 0.300 0.400 0.700 0.120 0.070 0.305 0.545 17,05 14,22 5,46 3,94 1,27 7,62 10,16 17,78 3,05 1,78 7,75 13,84 F E H G I J J K Dimensions – DPX4288-C L A B D C M E J J G N F F H 0.8025 / 20,38 0.1425 / 3,62 0.2405 / 6,11 0.3695 / 9,39 0 0.043 1,1 3 1 5 0.039 × 0.157 (4) 1,0 × 4,0 0.196 / 4,98 0.274 / 6,96 0.039 × 0.130 (2) 1,0 × 3,3 0.452 / 11,48 0.550 / 13,97 J K I G G Recommended Land Pattern Packaged 32 per tray A B C max max max 1.065 0.560 0.215 17,05 14,22 5,46 D typ E F G H I J K 0.155 0.050 0.400 0.800 0.120 0.070 0.305 0.545 3,94 1,27 10,16 20,32 3,05 1,78 7,75 13,84 1.2745 / 32,37 0.2845 / 7,23 0.9935 / 25,24 1.0945 / 27,80 0.692 / 17,58 2 4 0 (4) 0 F F O Recommended Board Layout Packaged 25 per tray A max B max 1.40 0.81 35,56 20,57 C max 0.51 12,95 D 0.580 14,73 E 0.124 3,15 F 0.005 1,27 G 0.035 0,89 I 0.855 21,72 K 0.229 5,82 L 0.378 9,60 M 0.091 2,31 N 0.311 7,90 O 0.753 19,13 J 0.118 3,00 H 1.303 33,10 Specifications subject to change without notice. Please check our website for latest information. © Coilcraft, Inc. 2007 Document 282-4 Revised 01/11/08