Voltage regulator (IC 7805)

IC 7805 is a voltage regulator integrated circuit. It is a member of 78xx series of fixed linear voltage regulator ICs. The voltage source in a circuit may have fluctuations and would not give the fixed voltage output. The voltage regulator IC maintains the output voltage at a constant value. The xx in 78xx indicates the fixed output voltage it is designed to provide. 7805 provides +5 volts regulated power supply. Capacitors of suitable values can be connected at input and output pins depending upon the respective voltage levels.

The regulator functions by using a diode to clamp the output voltage at 5 VDC regardless of the input voltage. Excess voltage is converted to heat and dissipated through the body of the regulator. If a DC supply of greater than 12 volts is used, excessive heat will be generated and the board may be damage. If a DC supply is less than 5 volts is used, insufficient voltage will be present at the regulators output.

For this project, input for all sensor should be equal to 5 volts. As mentioned before, all the sensors produce an analog output  within range 0- 5 volts. Therefore, this IC7805 are used to operate the system.