POWER TRANSFORMER Flyback Transformer for PoE E & E Magnetic Products Limited Providing Power to PoE devices with up to 13 Watts SCHEMATICS Flyback transformers designed for PoE (IEEE802.3af) powered devices with up to 13 Watts Designed for 250kHz switching frequency (continuous mode) with input of 33 - 57V Low Leakage Inductance Hipot voltage: 1500Vrms Operating temperature -40C to +85C. RoHS compliant version is available Custom design is also available ELECTRICAL SPECIFICATION @ 25C Part Number RoHS Part Number Pri : Sec Pri : Bias Inductance at 0A (uH 10%) 835-00848 835-00848F 1 : 0.166 1 : 0.50 127 114.3 835-00849 835-00849F 1 : 0.25 1 : 0.50 127 835-00850 835-00850F 1 : 0.50 1 : 0.50 835-00851 835-00851F 1 : 0.567 835-00852 835-00852F 1 : 0.667 Turns Ratio Inductance Leakage at Ipk Inductance (uH Min) (nH Max) DCR (mOhm Max) Ipk (A) Secondary Output Pri Bias Sec 1.25 255 310 24 1.0 Vout=3.3V,4.0A 114.3 0.95 222 348 39 1.0 Vout=5.0V,2.6A 127 114.3 0.65 199 308 65 1.0 Vout=12V,1.08A 1 : 0.50 127 114.3 0.80 290 355 66 1.0 Vout=19.5V, 0.67A 1 : 0.50 127 114.3 0.60 255 315 67 1.0 Vout=24V, 0.54A Notes: 1. Inductance is measured at 250kHz, 0.1Vrms, 0Adc. 2. Peak primary current, Ipk, is drawn at minimum input voltage. 3. DCR for the secondary is per winding. 4. Leakage Inductance measured between pins 3 and 4 with all other pins shorted. 5. Turns ratio is with the secondary windings connected in parallel. 6. Output of the secondary is with the windings connected in parallel. Bias winding output is 12V, 20mA. 7. Operating temperature range: -40C to +85C. The part temperature (ambient temperature + temperature rise) should not exceed the upper limit of the operating temperature under worst case operating conditions. Circuit design, component placement, PWB trace size and thickness, airflow and other cooling provisions all affect the part temperature. Part temperature should be verified in the end application. 2/F Block A, 94 Tokwawan Road, Kowloon, Hong Kong 1 Tel: (852) 2765 3888 Fax: (852) 2954 3304 PX202(02) Revised in 07/09 POWER TRANSFORMER Flyback Transformer for PoE E & E Magnetic Products Limited Providing Power to PoE devices with up to 13 Watts MECHANICAL DIMENSIONS .394 10.00 .550 13.97 MAX 1 .695 17.65 MAX .100 2.54 .098 2.50 5 .705 17.91 EE 835-008xx (DATE) 10 .051 1.30 6 RECOMMENDED PAD LAYOUT .028 0.71 .485 12.32 MAX .005-.020 0.13-0.51 REFERENCE OR GAUGE PLANE .040.010 1.020.25 .098.010 2.500.25 .394.010 10.000.25 Notes: 8. All dimensions are specified in inches mm with higher precedence in inches. Weight (in gram) : 6.0 typ. Tape & Reel : 160 / reel 9. Unless otherwise specified, all tolerances are .010 . 0.25 10. Coplanarity: .004 max. 0.10 SCHEMATICS 3 Pri 8 7 4 Sec 2 9 Bias 10 1 SCHEMATIC FOR MORE INFORMATION, PLEASE CONTACT HEADQUARTER 2/F Block A, Merit Industrial Centre, 94 Tokwawan Road, Kowloon, Hong Kong Tel: (852) 2765 3888 Fax: (852) 2954 3304 Email: eempl@eleceltek.com Website: http://www.eleceltek.com Information herein is for reference only and subject to change without notice. It does not constitute any representation, warranty or commitment of the company in respect of the products in any aspect. All logos, brands and product names mentioned herein are trademarks or registered trademarks of their respective owners. The company does not assume any liability arising out of the application or use of any product or circuit described herein. Copyrights 2007, E & E Magnetic Products Limited. 2/F Block A, 94 Tokwawan Road, Kowloon, Hong Kong 2 Tel: (852) 2765 3888 Fax: (852) 2954 3304 PX202(02) Revised in 07/09