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   - Capacitors
   - Transistors
 
+- [Regulator.](regulator/index.html)
+
 - [Inductors and motor driving.](inductors_motors/index.html)
 
 - [microcontroller](microcontroller/index.html)
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+<!DOCTYPE html>
+<html>
+<title>Electronics intro:  regulators.  </title>
+
+<xmp theme="journal" style="display:none;">
+<br>
+
+
+## regulators
+
+A regulator provides a stable (regulated) voltage at its given output voltage, up to its specified ouput current.  As an input,
+it reguires a voltage larger than its output.
+
+  [Datasheet](http://www.ti.com/lit/ds/symlink/lm3480.pdf) for the 3.3V 100mA regulator in the Fab inventory.
+
+
+___
+
+  ![picture](../images/regulator.png)
+
+  
+---
+
+
+
+</xmp>
+
+<script src="../strapdown-gh-pages/strapdown-gh-pages/v/0.2/strapdown.js"></script>
+</html>