MODEM MAGNETICS V.90 Modem Transformers • Provide isolation and balance while minimizing signal distortion and insertion loss in high-speed modem applications • Qualified per Bellcore TR-TSY-000357-1 • Approved by UL and CSA TM00408 • 2802A transformer is designed to match a 600Ω line to a 536Ω load • 2802B transformer is designed to match a 600Ω line to a 301Ω load • Minimum interwinding breakdown voltage of 1000 Vrms ELECTRICAL SPECIFICATIONS at 25° C Part Number Turns Ratio ± 2% Insertion Loss dB Return Loss dB Frequency Response dB DCR Ω max @ 1 kHz 300 Hz - 3500 Hz 200 Hz - 5 kHz Pri Harmonic Distortion dB Longitudinal Balance dB Sec 0 dBm, 600 Hz 300 Hz - 3500 Hz 2802A 1:1 < 0.80 > 30 < 0.1 48 48 < -82 > 60 2802B 1:1 < 2.8 > 20 < 0.2 165 170 < -90 > 60 SCHEMATIC 2802A 2802B 1 6 3 4 Primary Secondary ©2000 Bel Fuse Inc. Specifications subject to change without notice. 05.00 Bel Fuse Inc. 198 Van Vorst Street, Jersey City, NJ 07302 • Tel 201-432-0463 • Fax 201-432-9542 • www.belfuse.com T4-17 MODEM MAGNETICS V.90 Modem Transformers TM00408 TYPICAL SPICE TRANSMISSION MODEL 1.1 mH 44 42 1 4 2802A 20 pF 40 k 12 H 20 pF 3 6 4.3 mH 145 150 1 6 2802B 20 pF 150k 40 H 20 pF 3 4 MECHANICAL 2802A 2802B 0.470 [11.94] max 0.450 [11.43] 0.110 [2.79] 0.025 [0.63]Square Phosphor Bronze Solder-coated 0.650 [16.51] max 4 6 0.750 [19.05] 0.550 [13.97] Terminal 1 Identifier 3 1 Note: Unless otherwise specified, dimensions are nominal and in inches [millimeters]. ©2000 Bel Fuse Inc. Specifications subject to change without notice. 05.00 CORPORATE FAR EAST EUROPE Bel Fuse Inc. 198 Van Vorst Street Jersey City, NJ 07302 Tel 201-432-0463 Fax 201-432-9542 www.belfuse.com Bel Fuse Ltd. 8F / 8 Luk Hop Street San Po Kong Kowloon, Hong Kong Tel 852-2328-5515 Fax 852-2352-3706 www.belfuse.com Bel Fuse Europe Ltd. Preston Technology Management Centre Marsh Lane, Suite G7, Preston Lancashire, PR1 8UD, U.K. Tel 44-1772-556601 Fax 44-1772-888366 www.belfuse.com T4-18