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5.11. Measuring Voltages More Than 5V (Voltage Dividers)

Problem

You want to measure voltages greater than 5 volts. For example, you want to display the voltage of a 9V battery and trigger an alarm LED when the voltage falls below a certain level.

Solut...

From

Cover of Arduino Cookbook, 2nd Edition

Note

Use this with an Attiny 85 and a transistor to build a LiPo cutoff switch for RC Cars.