Specifications

solder the other pad, being careful not to use too much heat (or you’ll lift the part off the
board!).
__ Mount the 5.0V Voltage Regulator
Locate the large pad and the three small pads for the voltage regulator. Heat up the pad with
your soldering iron and melt a small amount of solder on the large pad, just enough to cover it.
Place the voltage regulator IC in place, and hold it down, then heat up the large pad on the
voltage regulator until the solder starts to flow. Hold your soldering iron on the pad for
another 5 seconds, then remove it and wait at least 10 seconds.
One by one, solder the three small three small leads to the pads, using enough solder to cover
the pad and get a good “tenting” on the leads without creating solder “blobs”. Wait at least 30
seconds between each pad to prevent the chip from overheating.
__ Mount the 10K resistors
Locate the 10K resistor (marked “103”) just below the processor. Solder it in place, using the
same procedure that you used for the .1 uF capacitor.
Locate the second 10K resistor, next to the voltage regulator. Tin ONLY the lead closest to the
voltage regulator. Place the resistor over the pads, and heat up the tinned pad. DO NOT solder
the other pad at this time… you’ll see why in the next step.
__ Mount the MOSFET
Locate the spot for the MOSFET, it’s just to the right and below the voltage regulator. Very
carefully remove the MOSFET from its package, you’ll notice that the pads on the PC board
are much wider than the lead spacing. This is done to make it easier to solder in place, and the
extra copper and solder provides heat sinking for it.
Lightly tin the ONE pad nearest to the right side of the board. With tweezers, hold the
MOSFET in place, centering it over the pad. If you have it right, the two leads on the other
side should just sit on the inside edges of the opposite pads. Heat up the lead over the tinned
pad until the solder starts to flow onto the lead, wait a few more seconds, then remove the iron
and let it cool for at least 5 seconds before you let it go.
Inspect the alignment of the MOSFET, making sure that the other two leads are sitting on their
pads. Once you are satisfied, solder the leads to the pads. The top pad is right next to the 10K
resistor that you previously mounted, add enough solder so that it solders that resistor too. One
pad, two components…
__ Mount the 2.2K resistor