Document 403 Planar Transformer For NSC LM5033 PWM Controller for IBC Applications The B0853-A was designed specifically for the National Semiconductor LM5033 high voltage PWM controller. This planar transformer can be used in push-pull, halfbridge and full-bridge topologies. It is ideal for use in high-current power supply applications such as open loop intermediate bus converters (IBC) and closed loop voltage mode converters. It offers high efficiency in a low-profile package and features a split secondary, a separate auxiliary winding and 1500 Vdc primary to secondary isolation. Coilcraft’s Planar Prototyping Kit C356 was used to design this transformer. No tooling or additional parts were required. To order the kit, contact Coilcraft or purchase on-line at http://order.coilcraft.com. Free evaluation samples of B0853-A are available by contacting Coilcraft or by visiting www.coilcraft.com. Part number1 B0853-AL_ Output power (W) 200 Input voltage range (V) 40 – 60 Output voltage nom (V) 10 Output current (A peak) 20 1. When ordering, please specify packaging code: B0853-ALD Packaging: D = 13″ machine ready reel. EIA-481 embossed plastic tape (200 parts per full reel). B = Less than full reel. In tape, but not machine ready. To have a leader and trailer added ($25 charge), use code letter D instead. Primary inductance2 min (µH) 46.8 Leakage inductance3 max (µH) 0.10 3 0.800 20,32 10 0.810 max 3 20,57 Turns ratio4 pri : sec : aux 5:4:4 2. Inductance measured on an Agilent/HP 4284 between pins 3 and 4 at 250 kHz, 0.1 Vrms, 0 Adc. 3. Leakage inductance measured between pins 3 and 4 at 100 kHz, 0.1 Vrms, 0 Adc with pins 6 and 10 shorted. 4. Turns ratio is with the secondary windings connected in series. 5. Storage and ambient operating temperature range: –40°C to +85°C. 6. Electrical specifications at 25°C. Dot indicates pin 1 1 DCR max (mOhms) Pri: 10.4 Sec: 4.0 Aux: 160.0 8 0.190 4,83 0.095 2,41 1 6 Pri 10 0.250 6,35 4 8 Sec 1 4 5 5 6 Ø 0.080 2,03 Aux Recommended Land Pattern 0.920 max 23,37 0.360 max 9,14 0.006 /0,15 Weight: Terminations: Tape and reel: 10 6 0.110 Ø 2,79 11.6 g Matte tin over nckel over brass 200/13″ reel 44 mm tape width Specifications subject to change without notice. Please check our website for latest information. © Coilcraft, Inc. 2007 5 Document 403 Revised 05/10/07