BXA15

BXA15 and BXA30 SERIES Design Note 100 Rev. 01 - Feb. 1999 • Safety and the low voltage directive • Electromagnetic Compatibility Immunity • Electromagnetic Compatibility Conducted and Radiated Interference • Telecom and Distributed Power Architecture Features • System Protection Features • Thermal Considerations • Input Impedance Considerations 1. Safety and the Low Voltage Directive The BXA15 and BXA30 series is intended to be supplied only from a SELV (Safe Extra Low Voltage) circuit or a TNV (Telecommunications Network Voltage) power source which are insulated from the AC mains by reinforced insulation. Basic isolation, tested to 1,500VDC, for EN60950 and UL1950, is provided. SELV TNV DC Distributed Power of 12V, 24V or 48V Central Office -48V Conducted Interference - Level B External Filter: The addition of an external capacitor enables the BXA15 and BXA30 products to meet VDE0871/8-B, EN55022-B and CISPR22-B conducted noise limits. The test set-up is per VDE 0877 Part 1 fig.4 with the load < 10 cm's away from the test converter. Input Voltage 48 Volt 24 Volt 12 Volt Recommended External Cap. Nippon Chemi-Con SXE series120uF, 100V ITW PAKTRON Capstick series part number 405K100CS4, 4uF @ 100V ITW PAKTRON 405K100CS4 2 * ITW PAKTRON 405K100CS4 capacitors in close parallel. 2. Electromagnetic Compatibility Immunity Good design practice dictates that the electronic system be immune to noise interference. This practice has now been encapsulated in European law in the form of the EMC directive. It is imperative that any system on sale in the European Union meets the terms of the EMC directive and thus carries the CE mark. To simplify system compliance to the EMC Directive, the BXA15 and BXA30 have been designed to meet and comply with the necessary immunity standards. Description Electro-Static Discharge Radiated Immunity Fast Transients/Bursts Surges Standard EN61000-4-2 Compliance Level 4kV Contact 8kV Discharge 10V/m 2kV 0.5KV (40 Ohm Generator, Secondary surge protection) For height critical applications, the ITW Paktron capacitor offers a low profile of