<p>Battery is 9v so I am using the regulator to change and settle the voltage at 5v. The sensor has two outputs, one digital and one analog. The digital output gives 1 if the ppm reading is very high and close to the threshold. Analog output varies and depends on the ppm readings. The digital pin is connected to PA2 and the analog pin is connected to PA3 which has ADC. LED is connected to PB1.</p>
<p>The following pictures are the real size of the traces and the cut.</p>