Bridge rectifiers on a model railroad

Semiconductor Discrete Semiconductor Products
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I’m integrating LED signals with turnouts on a model train layout. I use digital command control to operate it, so voltage is square wave DC. This is unsuitable for LED’s, so I need a small bridge rectifier for each turnout. Using a single one for the whole layout will create too much additional wiring. So I’m looking for a small bridge rectifier that can accept an input current of 16V square wave DC, convert to conventional DC and power a maximum of 3 LED’s. I will include a resistor in the wiring to each LED, either before or after the bridge rectifier, to reduce voltage to about 2.75V.

At the moment I’m looking at BAS4002ARPPE6327HTSA1, specs at https://www.infineon.com/assets/row/public/documents/24/49/infineon-bas4002aseries-ds-en.pdf?folderId=db3a30431f848401011fcbf2ab4c04c4&fileId=db3a304329a0f6ee0129a6dc9f802b68.

Does anybody have any comment?

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Welcome to the forum.

The part you chose should work assuming the 3 LEDs you use consume less than 33mA each (100mA) total.

If you need more current for the LEDs then a standard bipolar rectifier array is a better choice.

Considering the application, the higher voltage drop of bipolar diodes vs Schottky diodes won’t matter (except when calculating the series resistor values).

This bipolar bridge diode array can provide 10 times more current at about the same price.

Depending on the frequency of the input waveform, you may need to add a filter capacitor (e.g. 1 to 10 uF) at the output of the bridge to prevent flickering.

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