– Spring 2007 ECE 300 Christopher Boyd Anusha Gattupalli

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ECE 300 – Spring 2007
Christopher Boyd
Anusha Gattupalli
Timothy Poore
Project Assignment
Groups were assigned in class.
 Leaders for each group were specified.
 Dr. Green then described how to go
about doing the project.
 He specified what parts we would need
and where we could get them.
 He also gave us equipment to use like
the microscope and soldering iron.

Getting the Parts
We ordered 3 MSP430F449PZ chips
from Texas Instruments. (free samples)
 We then purchased a kit for the project
at the Ferris Hall Parts Store for $15.
 After we started working on the project,
we decided upon what types of sensors
we wanted and ordered free samples
from Analog Devices.

Project Goals
Over the course of the project, we were
expected to learn how to work as a team.
 Learn how to solder components like the
capacitors and the chip onto the board.
 Design a circuit to make the sensor work.
 Program the chip to analyze the voltage
from the sensor and display the
appropriate output on the LCD.

Soldering
Capacitors and resistors were mounted
first, to give us experience with soldering.
 We paid close attention to the direction
that the polarized capacitors were facing.
 Next we soldered the chip on the board.
 It would have been more difficult to solder
the chip on after the other parts were
placed on the board.

Soldering the Chip
The chip has 25 pins on each side.
 There are four ½ inch sides.
 We had to apply pressure to each pin as
we soldered it, in order to make sure a
good connection was made.
 On one side, the pins needed to be bent
slightly in order to make a connection
with the trace on the board.

Soldering (continued)
After we soldered the chip, we went
through and made sure that each of the
100 pins were properly connected.
 Then we soldered all the other
components like the JTAG connector
and the LCD.
 Finally, we mounted the voltage jacks
and soldered the wires to the
appropriate spots on the board.

Programming the Chip
First we tried to load the “Hello” program
to the chip.
 However, there were problems.
 Checked all the pins of the chip (again)
to make sure they were soldered on.
 After that, it still didn’t work. Turns out
the computer had a faulty parallel port.

Building the Sensor Circuits
Dr. Green had sent out an email with the
schematic for AD590 sensor circuit. We
built it exactly like the schematic.
 After tweaking the resistor pots
appropriately, it worked with Dr. Green’s
sensor program.
 Next was the AD22103, which was
simpler to set up (provided you don’t
have it reversed.)

AD22103 Program
Using the equation that we were given:
Vout=(Vs*3.3V)*[.25V+.028V/°C*Ta]
We plugged in Vs which was 2.869V
coming from the sensor board, and then
solved for Ta.
 This gives us:
T=41.0795*Vo-8.9286 (°C)
 However, Vo then had to be multiplied by
a scaling factor of .61.

AD22103 (continued)
In addition to the scaling factor for Vo,
the value was 100x what it should be,
which was appropriate since this is
needed for the LCD display.
 However, this meant that any value
added to or subtracted from the Vo
needed to be multiplied by 100.

AD22103 Chart
Any Questions?
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