2778A

MODEM MAGNETICS Global V.90 and V.34 Transformers TM00403 • • Intended for use in high-speed modem applications Features very low interwinding capacitance, wellisolated windings, and low total harmonic distortion • Designed to comply with EN60950 requirements for a reinforced insulation barrier with a working voltage of 250V Approved by UL, CSA and BABT Minimum interwinding breakdown voltage of 3000 Vrms • • Qualified per Bellcore TR-TSY-000357-1 • ELECTRICAL SPECIFICATIONS at 25° C Insertion Loss dB Frequency Response dB DCR Ω max Longitudinal Balance dB Part Number Modem Speed Turns Ratio ± 2% Return Loss dB Harmonic Distortion dB @ 1 kHz 300 Hz - 1 kHz 100 Hz - 4000 Hz Pri Sec > 86, -9 dBm, 300 Hz > -80, -10 dBm, 600 Hz 300 Hz - 3500 Hz 2778A V.90 1:1 < 1.2 > 18 < 0.5 69 69 > 60 2778B V.34 1:1 < 1.2 > 20 < 0.5 69 69 > 60 SCHEMATIC 2778A 2778B 1 6 3 Primary 4 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 T4-7 MODEM MAGNETICS TM00403 Global V.90 and V.34 Transformers TYPICAL SPICE TRANSMISSION MODEL 2778A 58 typ 18 mH typ 58 typ 1 2778B 58 17 mH 58 6 10 pF 45 k 15 H 3 10 pF 25 k 10 H 10 pF 4 MECHANICAL 2778A 2778B 0.565 [14.35] max 0.118 [3.00] 0.710 [18.03] max sq. 0.50 [12.7] 0.020 [0.508] sq. wire 3 0.300 [7.62] 1 4 6 Note: Unless otherwise specified, dimensions are nominal and in inches [millimeters]. ©2000 Bel Fuse Inc. Specifications subject to change without notice. 05.00 CORPORATE Bel Fuse Inc. 198 Van Vorst Street Jersey City, NJ 07302 Tel 201-432-0463 Fax 201-432-9542 www.belfuse.com FAR EAST 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 EUROPE 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 T4-8