Document 140-1 Mag Amp Toroids – G642X Series This product is not RoHS-compliant. Contact Coilcraft for current status or possible alternatives. These low cost saturable reactor (mag amp) coils are designed to regulate switching power supplies operating at frequencies from 20 kHz to over 100 kHz. In multi-output circuits requiring tight crossregulation, mag amp control is simple and more cost-effective than adding conventional linear voltage regulators to each output. Mag amps are also particularly advantageous where load current exceeds 1 or 2 amps, because of their efficiency and low heat dissipation. Coilcraft Designer’s Kit No. P206 contains samples of all values shown. To order, please contact Coilcraft or visit http://order.coilcraft.com. Advantages • Higher efficiency than linear regulators, especially at higher currents • Simple cross-regulation of multi-output supplies • Lower EMI • Frequency range of 20 kHz to over 100 kHz • Standardized construction for maximum economy Electrical Specifications G6421-A Current1 Volt-time product (typical) Weight (g) G6422-A G6423-A 1A 93 v-µsec 1A 133 v-µsec 1A 372 v-µsec G6424-A 5A 42 v-µsec G6425-A 5A 66 v-µsec G6426-A 5A 186 v-µsec 4.4 5.5 9.6 5.2 6.6 12.8 1. Based on 40°C maximum temperature rise. 2. Operating temperature range –40°C to +85°C. 3. Electrical specifications at 25°C. Specifications subject to change without notice. Please check our website for latest information. © Coilcraft, Inc. 2008 Document 140-1 Revised 12/03/02 Document 140-2 Mag Amp Toroids - G642X Series Dimensions 1 A 4 1 2 +0.025 0.600 ±0.010 15,24 ±0,254 2 2 NC 4 0.150 –0.010 B +0,635 3,81 –0,254 0.040 ±0.003 dia 1,02 ±0,08 Part number 1 G6421-A G6422-A G6423-A G6424-A G6425-A G6426-A 2 0.250 ±0.010 6,35 ±0,254 4 A max 0.85/21,59 1.00/25,40 1.25/31,75 0.90/22,86 1.05/26,67 1.30/33,02 B max C max 0.65/16,51 0.65/16,51 0.65/16,51 0.55/13,97 0.55/13,97 0.55/13,97 0.825/20,96 0.825/20,96 1.150/29,21 0.825/20,96 0.825/20,96 1.150/29,21 C Test Circuit The test circuit below can be used to test the volt-time product supported by each of the mag amp coils. Apply the square wave to the coil and observe the current waveform (voltage across the series resistor). Increase the applied voltage until a spike appears at the end of each half cycle, indicating core saturation. Saturation is defined as the point at which the magnitude of the spike has become twice the peak value of the square wave. (Actually the current square wave is not flat but gradually increases due to the magnetizing current.) To record the volt-time product, multiply the applied peak voltage by the time required to reach saturation and divide by two. The series resistor should be as small as possible, without loading the square wave supply. If the square wave generator is powerful enough, the differential amp may not be necessary. + + + Square Wave Generator Differential Amplifier V Applied Inductor under test – RS Scope V Applied 0 – Specifications subject to change without notice. Please check our website for latest information. © Coilcraft, Inc. 2008 Vr (Scope) t v 0 2v t – Document 140-2 Revised 12/03/02