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4. Integrated Circuits (ICs): This kit contains three types of IC components: a voltage regulator,
the charge pump, and a Hall effect sensor (which will be installed later on the sensor board).
These components are packed in a static-protective silver bag along with the PCB (because it
also has a few ICs already installed on it). In general, ICs are quite sensitive to static electricity
and can easily be damaged. Humans are not sensitive to static electricity at these low, yet
damaging levels; in fact, most people can’t even feel a static discharge less than 1000 volts!
So it is easy to damage these components without even knowing it. Before touching an IC or
the PCB, and often while working with them, ground yourself preferably by touching something
grounded to the mains like the metal chassis of a plugged-in amplifier, or a refrigerator. At
the very least touch a large conductive object like a metal desk or filing cabinet. In our lab,
we wear conductive, anti-static bracelets that are connected to the electrical main’s ground.
When soldering ICs, try to prevent the IC from getting too hot. As a rule of thumb don’t keep
your iron on any leg longer than two seconds, and make sure the chip stays cool enough to
touch. Solder one leg at a time and let the chip cool off before proceeding to the next leg.
ICs have a specific orientation. If you install them wrong, your VPM-1 will not work and you could
damage or destroy the IC. Please pay close attention to the pictures and instructions so as not to
install them backwards. See “Figure 5: Main Board Component Values and Locations” on page
13, and the graphics on the PCB, to help you correctly orient the ICs.
a. Voltage Regulator, 78L05 (U5): This component takes the 9 volts from the power jack and
converts it to 5 volts to run the microcontroller. It is shaped like a three-quarter moon. Install
the voltage regulator on the board in the correct orientation (it is polarized) (40). Bend the
leads out on the other side of the board (41). Solder and clip the leads (42,43).
40
41
42
43