e. Noise Suppression Devices An amorphous noise suppression device is unique and completely different from conventional noise filters. Conventional noise prevention products focus on somehow minimizing the noise after it's been created, by typically trying to absorb the noise, and so their effectiveness in noise reduction is directly influenced by frequency of the circuit. Amorphous noise suppressing devices, on the other hand, focus on the source of the noise and work to prevent or minimize the noise before it has a chance to develop. The source of the electronic circuit noise is the rapid change of current or voltage, and the effectiveness of the amorphous cores in eliminating this noise is independent of frequency. An amorphous noise suppression device is a product that takes full advantage of the unique magnetic characteristics of the cobalt based amorphous alloy. Toshiba Materials offers two noise suppression devices, "AMOBEADS8" and "SPIKE KILLERS". AMOBEADS" deliver excellent noise suppression results and are convenient to use by simply being slipped over the leads of the semiconductor device. "AMOBEADS" are also available with a lead thru and in a surface mount configuration. "SPIKE KILLERS", which are larger in size than "AMOBEADS", most often are wire wound and are effective in eliminating or minimizing higher noise levels. Noise Suppression Device co FH . Joy 755>t et* 2e* aee* RC Snubber Magnetic Snubber e* ,oe** + . . . as ge Basic Snubber Circuit Diagram est? a a 2 Bit] 4 ne aaennenh % af Amorphous s* e x a. - %. ~ * . ~ | . e* * %. "4 eae Ferrite a at* ee ee aig 7 ih e SS OG! 7 a0. 80 \, : H [A/m] Noise Suppression Devices (100 kHz, RT) B-H Curve (typical) Example for Noise Suppressing Effect (Chopper Converter) With an excellent saturable characteristic, "AMOBEADS suppress the reverse recovery current of the diode and decrease the noise that was occurring. When the current for diode reverses and tries to go into the recovery condition, the "AMOBEADS" displays a large inductance and oppose the generation of the recovery current. In this instance, a soft recovery is possible for core material with a smaller coercive force. Output Noise Diode Current 1 A/div ae ot ae Leg Without Countermeasure With AMOBEADS (AB4x2x8W) AB/LB/7 SS Senes Standard Specifications AMOBEADS Type No Finished Dimensions [mm] Core Size [mm]*! Total Flux* AL value*? Insulating | Packing . O.D. max | |. D. min | H.T. max O.D. I. D. H.T. @c[uWb] min L[ ZH] min Cover *7 Unit AB3X2X3W 4.0 1.5 4.5 3.0 2.0 3.0 0.9 3.0 AB3X2X4.5W) 4.0 1.5 6.0 3.0 2.0 45 1.3 5.0 2000 AB3X2x6w | 4.0 15 75 3.0 2.0 6.0 1.8 7.0 PBT case | incs/box] AB4X2X4.5W| 5.0 15 6.0 4.0 2.0 45 27 9.0 Blue AB4X2X6W 5.0 1.5 7.5 4.0 2.0 6.0 3.6 12.0 AB4X2X8W 5.0 1.5 9.5 4.0 2.0 8.0 4.8 16.0 AMOBEADS with lead Finished Dimensions [mm Core Si. ial 4 xe *8 : : Type No. [mm] ore Sizeimm) | i, lrotal Flux|AL value Insulating, Packing A B Cc D E F O.D.| LD.) HT} [Al | @tuWb)} LIvH)) OY mit LB4X2x8F | 6.0max| 16.0max| 12.0max 4.2+0.5 |14.0+1.0 |@1.25+0.1 PBT case | 1,000 40 | 20/80 | 80 48 16.0 Black LB4X2X8U_| 6.0max| 20.0max| 12.0mak 4.0+0.5 | 5.0+1.0 |@1.25+0.1 " , " : min min jac [pcs/box] B A LB4X2X8F fe LB4X2X8U a t ; o * , 0% 4 064 fA Cc] B 5, 09%, 8 F os E D >IKF El. AMOBEADS SMD Type AMOBEADS Type No. Finished Dimensions [mm] Lead Core Size [mm] *! lo ** |total Flax |AL value Insulating ete width | length | height | width x thickness} O.D.| I.D. | H.T [A] @cluWb] L[UWH] Cover*7 [pcs/reel] AB3X2X3SM |5.0+0.3 |5.0+0.3 /4.0+0.3 | (1.8x0.35) 30 | 20] 30 6.0 0.9 min 3.0 LCP case 2,000 AB4X2X6SM_|6.0+0.3 |8.0+0.3 [5.0+0.3 | (1.8x0.52) 40 | 20 | 60 9.0 3.6 min| 12.0 Black 1,000 Recommended Land Pattern (mm) Taping Spec.(mm) 8 4 es | Ye siete AB3X2X3SM [_] le4 [| BE) fea [ea] 2, 9.4 ea SSeS 12 4 tr -o-fo--0--o].6--6-- | [ J AB4X2X6SM Je4 [| es a + 33 14.7 {A ia ; | Paper Reel (330) pe SPIKE KILLER . . _ #6 . *1 A #1 M Flux 1 *5 | Coercive | Rectangular : Type No, _[Finished Dimensions [mm]| Core Size [mm] Effective core Path Length | Total Flux Force *5| Ratios insulating O.D. LD. | HT O.D.} LD. | HT Ae[mm2] Lm [mm] @c[uWb]min | Hc[A/m] Br/Bm[%] Cover SS10X7x4.5W | 115 | 58 | 66 10.0] 7.0 | 45 5.06 26.7 4.73 59 / PET case ss14xex4a5w | 158 | 68 | 66 140| 80 | 45 10.1 34.6 9.46 max | SOmin Black x 1 Reference Value 2 Minimum Guarantee on Measuring Condition : 50kKHz, 80A/m(sine wave), R.T. x3 Measuring Condition : 50kHz, 1V, 1 turn, R.T. *4 Typical Value, using a cross section of lead Se & a *5 Measuring Condition : 100kHz, 80A/m (sine wave), R.T. +6 Tolerance +0.2 [mm] 7 UL94V-0 approved material S S y<"AMOBEADS" sample kits are prepared. Please ask to sales department. yx"AMOBEADS" and "SPIKE KILLER ": Registered trademarks of TOSHIBA MATERIALS Co., Ltd. yx"AMOBEADS "and "SPIKE KILLER : : Resistered in U.S.A., France, Germany, U.K., Japan. -9- >Elolss Or NOoOlise| Siretipess cipiel trair Creractaristics Application of Amorphous Noise Suppression Devices Ce ~~ | Ys 6 O Chopper Converter AB e Oo 1] Flyback Converter AB Control Circuit for Motor . AB I AB foe . RS Motor Driving Circuit Forward Converter AB eS. Ot 09 O = I O AB Push-pull Converter Characteristics (Typical value) 10000 1000 100 Pfe [kW/m3] Typical value R.T. Sine Wave 0.01 0.1 1 AB | IT] Coreloss Characteristic [AMOBEADS ] - 10 - 100 AB4x2x6W WwW 10 r a oO 3 g AB3x2x6w 1 AB3x2x4. i? AB3x2x3W Typical Value 0.1 1k 10k 100k 1M Frequency f [Hz] Frequency Characteristics of Inductance Oo lo a s > & 8 oO 20 40 60 80 100 120 Temperature ['C] Flux(@) Decline Ratio vs. Temperature Effects of Noise Suppress a ey) S lon OY ANIOS= eaea \E) Spike Voltage Suppression Spike voltage can be re- duced and ringing phenom- ena can also be prevented by AMOBEADS, and also Schottky barrier diode (SBD) can be protected from over withstand voltage. Frequency : 500kHz Output Voltage - Current >5V-20A Without Countermeasure AMOBEADS AB4 x2 x4.5W" Diode Voltage Vb 10V/div Diode Current el Output Noise Reduction When the ferrite replaced to AMOBEADS at the second- ary output diode (FRD) of the forward converter circuit, the output noise can be tremen- dously reduced, not only noise peak level but also am- plitude range. Frequency : 150kHz Output Voltage - Current > 15V-10A Output Noise VN 20mv/div Primary Surge Voltage When the ferrite replaced to AMOBEADS at the secondary output diode (SBD) of the for- ward converter circuit, the output noise and harmful influ- ence to the primary stage can be reduced. These effects are based on the inclination of the actual BH curves between amorphous and ferrite materi- als. Frequency : 250kHz Output Voltage - Current :5V-15A Output Noise Actual BH Curve MOS-FET Drain-Source Voltage Vps 200V/div Output Noise VN 50mv/div BH characteristics of Amobeads BH characteristics of Ferrite Pe ? -11l-