These circuits can be used to supply low current DC accessory circuits by tapping into the DCC track supply Bus. This might be done if a regular DC supply was not available and the power required by the accessory was small.
Full Wave Rectification of DCC Voltages
The next diagram shows the effect of rectifying a DCC voltage with a full wave bridge. The voltage at the output of the bridge is equal to the input minus the drop across the diodes.
The small tick in the output of the bridge occurs when the polarity of the H-Bridge reverses. The size of the ticks is largely determined by the efficiencies of the H-Bridge and rectifier bridge and in most cases can be ignored. This is why filter capacitors are not needed for decoders.
Diodes used to rectify DCC should be Schottky or high speed silicon types. Diodes of the 1N4000 and 1N5400 series are not suitable for this application due to their slow turn-off times.
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