sensors selection help!!!

[Munib]

I am a final year student of electronics engineering doing a project WIRELESS SENSOR NETWORK.

Now i have to select different sensors for my project and i need help in this regard

Which sensors i should choose?

I know this a stupid question because i should know my needs by myself but as this is a student project so the basic purpose is learning. So any kind of sensor selctions are welcomed

But there are just two constraints that sensors must no be costly(maximum of 6-7
US dollars will be ok) and keep in mind that i have to interface these sensors to a microcontroller(i.e PIC18F452 having built in 10 bit ADC so no prolem whether sensors are digital or analog)

Plz try to give the manufacturer name, part number and approximate price

 

[echo47]

Student project, eh? I suggest something practical:
1. Fluid level - liters of beer remaining in the keg.
2. Weight - grams of pizza remaining in the box.
3. Sound pressure level - decibels//micropascal of cheering during the television soccer game.


Someone else, please give this fellow a serious answer.

 

[flatulent]

IC temperature sensors are low cost. So are light level sensors which you will have to do some designing to go from the Cadmium Sulfide (CS) optical sensitive resistance sensors to your ADC. They are cheap from Tandy/Radio Shack company.

 

[IanP]

You can try these two sensors:
1. 3-pin temperature sensor 0-100degC LM335DZ (can operate directly from +%V)
2. Hall efect sensor with proportional output SS495A (Honeywell)

They should be within your target price.
You may need additional op-amp to shift levels/amplify or condition signals..

 

[nicleo]

Temperature monitoring is one of the popular application in industries. You may try to learn sensors with different interfaces:

DS18B20
Description: High-Precision 1-Wire Digital Thermometer
Interface: 1-Wire serial bus
Manufacturer: Maxim
Unit Price: 1.76USD

DS18B20-PAR
Description: 1-Wire Parasite-Power Digital Thermometer (DS18B20-PAR does not need an external power supply because it derives power directly from the data line ("parasite power"))
Interface: 1-Wire serial bus
Manufacturer: Maxim
Unit Price: 1.76USD

DS1721
Description: Digital Thermometer
Interface: 2-wire / SMBus
Manufacturer: Maxim
Unit Price: 1.61USD

DS1722
Description: Digital Thermometer with SPI / 3-Wire Interface
Interface: SPI / 3-Wire
Manufacturer: Maxim
Unit Price: 1.10USD


You may also find temperature sensors with different interface (2-wire, 3-wire, etc) from Texas Instruments and National Semiconductor. For your information, Maxim IC, National Semiconductor, and Texas Instruments offer LIMITED FREE samples for customer to evaluate.