I tried 4 of them at 3.3, 5 and 9 volts output with 12 volts input. In all cases the output voltage was much too low to operate the micro controllers. Even though the adj pads were not shorted the potentiometer would change the output. If the adjustable pads are shorted the I still could not get 5 volts output. On the plus side they are small and inexpensive.
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