Zoombak A-GPS Universal Locator Guia do Utilizador descarregar pdf (Página 18)

11 | P a g e

signals from the RF receiver when user input is given in the form of a voltage and runs it through

a resistor to supply logic data to the control circuit. It also receives voltage from the control

circuit through a transistor to turn on a 12 V relay that supplies power to sound the alarm. This

is required due to the low current output from the PROM not being able to energize the relay.

Power is stored within a rechargeable battery pack. This system allows for the storage and

distribution of power to the other subsystems of the design without the threat of overload. As

such, it is an integral part of the design.

The components of the power system serve various purposes to the functioning of the

overall system. However, there are also some changes that the design team would recommend if

pursued to the manufacturing stage. For example, the voltage regulators, which are needed to

keep the voltage in a circuit close to a certain desired value, in the prototype are at a fixed

amount of 5 volts, which, given the differing power needs of the other subsystems, put them at a

disadvantage due to the risk of overheating. In the prototype, the design implemented heat sinks

to counteract the overheating of the voltage regulators. The design team, however, has

recommended using variable voltage regulators to eliminate the need for heat sinks. The relays,

when energized, close contact-sets to complete certain circuits, thus acting as a kind of switch

where needed. True to their name, the resistors are needed at different points throughout the

circuitry of the power system to restrain and control the amount of electrical current that can pass

through different parts of the circuit. The magnitude of the resistor can vary depending upon the

amount of current needed through the circuit. Each of these components plays a crucial role in

the performance of the system, and as seen with the voltage regulators, more efficient and less

costly changes can be conceived for future adaptations of the system.

1 2 ... 13 14 15 16 17 18 19 20 21 22 23 ... 85 86

Sem comentários

Zoombak A-GPS Universal Locator Guia do Utilizador Página 18