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Filter components are necessary to reduce the input ripple current and output voltage noise. Without any input filtering, the sawtooth currents ofthe switching power lines T-To and T-To would flow in the supply line. Since this AC current can be as great as lA peak, voltage interference with other components using this supply line would likely occur. Use of a pi-filter can reduce the input ripple current to about ImA peak. Recommended values are a 20ccH inductor prior to the connection ofthe supply to the power plane. A lOccF tantalum capacitor with a 0.33ccF ceramic capacitor is ad- equate for the input bypassing . The inductor must be rated for at least 2A or a DC resistance of 0.1 I . An example of a low-cost inductor is part number 51591 from Pulse Engi- nea'ing. Output voltage filtering is achieved with a 0.33ccF capacitor connecting each VOUT pin of the diode bridge to ground. Short leads and close placement ofthe capacitors to the bridge provide optimum high frequency bypassing. Us- ing correct bypassing techniques, 600kHz ripple ofless than SmVp-p is achievable. High frequency noise bursts coincid- ing with the switch times are approximately 20mVp-p. Inductance of 20ccH in series with the output loads will significantly reduce the noise seen by the loads.