Specifications

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into place. One being that this LED should provide enough light to light up in dark
areas. This means that the LED must operate between a wavelength 450 and
760 nm. Furthermore, there should be a correlation between the frequency and
current. This was taken into consideration for the reason that the LEDs would
draw a collective amount of current. One LED that was researched was the
BIPOLAR T-1 ¾ (5mm) from Fairchild Semiconductor™.
The BIPOLAR T model number MV5491A included two different frequencies
spectrums, red, which operated between 1.6V and 2.0V and green, which
operated at between 4V and 1.9 V. This specific LED had various characteristics
that would prove efficient for the Breathalyzer System design. There were many
different LEDs that were researched. Some of the common parameters that were
needed to get the correct LED for this project were low cost, low power,
sustainability, and size. These four characteristics would shape the design layout
for the LEDs aspect.
The rating that characterized this as a prominent choice for the design was that
the MV5419A peak forward current and power dissipation. The size would be
well more than sufficient for our design which is shown in Figure 2.5.1.1. As
mentioned before, implementing this LED on the Breathalyzer system design
would very effective mainly for the reason that it is low in cost, low in power, and
the size requirements will fit the design. Since this Breathalyzer system design
will be used in any occasion during the day this means that this LED should be
effective during any time period. Therefore, this will require an LED that will be
provide enough light to be seen in any time of weather. The advantage of having
this LED on the Breathalyzer system design is that even if the person is outside
in the cold of night and can’t see the LCD display, this light will indicate whether
the user is coherent enough to drive the vehicle.