EE $212$ Project

Design $($on paper$)$ a RPM $($revolution per min.$)$ measuring instrument. The instrument

will have four $7-$segment displays therefore numbers from $0000-9999$ can theoretically be

displayed on it$.$ However It may be difficult to obtain high precision therefore your

display will show the RPM in $10$ RPM steps. For example the display may show numbers

like $0810,0920,0120,5730$ etc..; so you may have maximum $1000$ levels instead of

$10000$ levels to simplify the design.

The current will be $20mA$ in each segment of the display.

The instrument does not display numbers if the RPM is less than $500$ and if it is higher

than $8000.$ Instead it displays two words SLOW or HIGH.

Design the circuit such that on the $7-$segment display the following word will appear

accordingly: SLOU $($since W cannot be displayed on a $7$ segment display$)$ if the RPM is

less than $500$ and; FASt if the RPM is higher than $8000.$ Between these values the correct

RPM is displayed numerically.

Find the components from the market. You will first convert RPM to a voltage; than you

may use an ADC to convert it to a digital quantity. Finally it is to be displayed.

Design with minimum cost. Write the total cost of the project approximately.

Explain the operating principle of the designs $($evaluation is mainly on this explanation$).$

Note that there is a very large number of possible designs and each student will make

his$/$her their own design. A perfect design is not expected. Do your best.