How to interface ADC 0808 with Sensors

adc0808 applications

Hi All,

Can anyone help me how to interface ADC0808 with different sensors,
As i am using 8051 microcontroller & A/D convertor is ADC0808.I know interfacing of microcontroller with A/d convertor,but not with sensors.

I am using sensors like PIR sensor,LPG Gas sensor,Door sensor & many other.

Reply me soon.

Thnx & Regards,

Jitendra Kumar,
Pune.

adc0808 interfacing

Hello,

ADC0808 can be operated with 0-5 V input range for most applications. If you have a regulated 5V supply, Vref could be simply connected to VCC. The sensors you mentioned may have different output signal charateristics, the datasheets should tell. Basically, the preprocessing of sensor signals to produce standard output, e. g. voltage signals, is an object of industrial instrumentation or analog electronic textbooks and couldn't be treated within a few words.

At best, a sensor could have an output signal that can be directly interfaced to an ADC (e. g. ADC0808) without preprocessing. But this depends also on exact application, required detection limits and acuracy and also used sensor type. You're referring to a LPG gas sensor. But that could be a Figaro TGS sensor, a Nemoto pellistor or possibly a miniaturized NDIR sensor. Each of them requires special signal preprocessing.

I also think, whoever defined the project should have given some more detailed hints about possible ways to proceed. However, if it's based primary on your ideas, you should probably start with a sensor not needing very complex signal processing.

Regards,
Frank

0808 adc

use differntial opamp(instument amp).

adc0808

look to the attachment will great help u