78250 SERIES Converter Transformers SELECTION GUIDE 78250/78250M FEATURES Parameter Conditions MIN TYP MAX Units Primary Inductance, L P 10kHz, 100mV 1.0 2.0 2.5 mH Leakage Inductance, L L 100kHz, 100mV 2.0 3.0 H Interwinding Capacitance, C WW 100kHz, 100mV 69 90 pF D.C. Resistance, R DC <0.1VDC 1.0 2.0 Volt-time Product, E T 5kHz, 5V 50 Vs Maxim Compatible Isolation to 4kV SELECTION GUIDE 78250V/78250MV Surface Mount Options Parameter Conditions MIN TYP MAX Units Primary Inductance, L P 10kHz, 100mV 1.0 2.0 2.5 mH Leakage Inductance, L L 100kHz, 100mV 35 40 H Interwinding Capacitance, C WW 100kHz, 100mV 9 12 pF D.C. Resistance, R DC <0.1VDC 1.4 1.8 Volt-time Product, E T 5kHz, 5V Toroidal Construction Standard Pinout UL 94V-0 Package Material Fully Encapsulated Low Profile Industrial Temperature Range DESCRIPTION The 78250 series of converter transformers are specifically designed for use with Maxim chipsets to provide isolated RS232 interfaces. Carefully controlled turns ratios ensur e consistent performance whilst a toroidal construction minimises EMI. The surface mount devices are fully compatible with CECC00802 to 280C which allows them to be placed and reflowed with IC's thus reducing time and cost in production. Vs ABSOLUTE MAXIMUM RATINGS Operating free air temperature range Storage temperature range Lead Temperature 1.5mm from case for 10 seconds Peak current IPK Isolation voltage 78250(M) (flash tested for 1 second) Isolation voltage 78250V(M) (flash tested for 1 second) All specifications typical at TA=25C. www.dc-dc.com 50 -40C to 85C -50C to 125C 300C 300mA 1500Vrms 4000Vrms 78250 SERIES Converter Transformers MECHANICAL DIMENSIONS 6 Pin DIP 9.52 max Top View 1 8.89 max Primary Secondary 6 2 78250 4 3 XYYWW 6.35 3.440.50 0.30 0.20 0.63 0.53 10.16 6 Pin SM 2.54 12.70 9.52 max Top View Primary 1 8.89 max 78250M XYYWW Secondary 6 2 5* 3 4 6.35 0.30 0.20 0.90 2.54 * Pin 5 is connected to secondary centre tap. All dimensions in mm XX.XX 0.25mm. All pins on a 2.54mm pitch and within 0.25mm of true position. C&D Technologies (NCL) Limited reserve the right to alter or improve the specification, internal design or manufacturing process at any time, without notice. Please check with your supplier or visit our web site to ensure that you have the current and complete specification for your product before use. (c) C&D Technologies (NCL) Limited 2000 NMP 78250.2 No part of this publication may be copied, transmitted or stored in a retrieval system or reproduced in any way including, but not limited to, photography, photocopy, magnetic or other recording means, without prior written permission from C&D Technologies (NCL) Limited. Instructions for use are available from www.dc-dc.com C&D Technologies (NCL) Ltd Tanners Drive, Blakelands North Milton Keynes MK14 5BU, England Tel: +44 (0)1908 615232 Fax:+44 (0)1908 617545 email: info@cdtechno-ncl.com www: http://www.dc-dc.com 0.63 0.53 C&D Technologies (NCL), Inc. 8917 Glenwood Avenue, Raleigh NC 27612, USA Tel: +1 (919) 571-9405 Fax: +1 (919) 571-9262 email: info@us.cdtechno-ncl.com