Document 372-1 Planar Magnetics For National Semiconductor LM5025 and LM5034 This planar transformer and planar inductor pair is designed specifically for the National Semiconductor LM5110 Gate Driver and LM5025 Active Clamp Voltage Mode PWM Controller. These parts are also specified by NSC for use with their LM5034 Dual Interleaved Controller. The B0357-B transformer is engineered for use in high current telecom power supply applications that require high efficiency in a low-profile package. The main winding of the B0358-C inductor serves as an output choke, while the auxiliary winding controls input current to the PWM. Request free evaluation samples by contacting Coilcraft or visiting www.coilcraft.com. Transformer Part number B0357-B Output power (W) 100 Output voltage (V) 3.3 Output current (A rms) 30.0 Primary inductance1 min (µH) 320.0 Leakage inductance2 max (µH) 0.55 DCR max (mOhms) Primary: 55.0 Secondary: 1.0 Pri/sec isolation (Vdc) 1500 1. Inductance measured on an Agilent/HP 4284 between pins 1 and 2 at 250 kHz, 0.1 Vrms, 0 Adc. 2. Leakage inductance measured between pins 1 and 2 at 100 kHz, 0.1 Vrms, 0 Adc with secondary pins shorted. 3. Storage and ambient operating temperature range: –40°C to +85°C. 4. Electrical specifications at 25°C. Dimensions Schematic 0.920 max 23,37 0.125 3,18 1 1 4 0.810 max 20,57 0.400 10,16 3 0.250 6,35 2 2 0.080 Ø 2,03 Pri 4 0.200 5,08 3 1 0.800 20,32 Sec 2 4 3 Recommended Land Pattern Ø 12 : 2 0.110 2,79 0.360 max 9,14 0.006 /0,15 Tape and reel: 200/13″ reel 44 mm tape width Specifications subject to change without notice. © Coilcraft, Inc. 2005 Document 372-1 Revised 10/04/04 Document 372-2 Planar Magnetics for National Semiconductor LM5025 Output Inductor Inductance1 at 0 Adc (µH) 2.0 ±10% Part number B0358-C I rated Adc 30 Isolation2 (Vdc) 1500 DCR max (mOhms) Main: 1.7 Aux: 900.0 Isat3 (A) 38 Irms4 (A) 36 1. Inductance measured on an Agilent/HP 4284 between pins 3 and 4 at 10 kHz, 0.1 Vrms. 2. Isolation measured from pin 1 to pin 3. 3. DC current at which inductance drops 10% (typ) from its value without current. 4. Average current for a 40°C rise above 25°C ambient. 5. Storage and ambient operating temperature range: –40°C to +85°C. 6. Electrical specifications at 25°C. Typical L vs Frequency Typical L vs Current 1000 Inductance (µH) Inductance (µH) 1000 100 10 100 10 1 1 1 0.1 10 100 1000 10000 0.1 Schematic 0.920 max 23,37 3 0.800 20,32 1 Main 4T 4 4 4 0.810 max 20,57 2 100 Current (A) Dimensions 1 10 1 Frequency (MHz) 0.310 7,87 0.250 6,35 0.310 7,87 0.250 6,35 1 Aux 13T 2 3 2 Ø 0.080 2,03 3 Recommended Land Pattern Ø 0.110 2,79 0.360 max 9,14 0.006 /0,15 Tape and reel: 200/13″ reel 44 mm tape width Specifications subject to change without notice. © Coilcraft, Inc. 2005 Document 372-2 Revised 10/04/04