How to use 16Bit ADC with PIC16877

[d_hamen]

Hello everbody;

I have to use 16bit ADC with pic 16f877 in my project. I know that 16f877 has 10bit ADC. so I have to use extra device with my pic but what is that converter. or is there something to do different?

Please help!!!

 

[Beowolf]

16Bit ADC

it is completely different! To achive that resolution, you need to pay special attention to PCB desgn. Also, you ned an extra code to interface the ADC. Choose an apropriate ADC, and see it's Data sheet. Ask in analog circuit sub-furum for layout

 

[IBO]

Re: 16Bit ADC

no extra components required, just gnd the six most significant bits.

i think so color=darkblue][/color]

 

[xunzhaoziwo]

Re: 16Bit ADC

no extra components required, just gnd the six most significant bits.

i think so color=darkblue][/color]

I think IBO is right. When we are using a ADC which has more bits than the processor, we always ignore (Ground them) the low bits of the ADC.
So, here, in your situation, you just need to ignore (Ground them) the lower 6 bits.
That's OK!

 

[d_hamen]

Re: 16Bit ADC

but I have to use all of the bits. so if I ignore them I will carry the data on only ten bits. But I have to carry them on 16 bits. with no ignore.

 

[ldanielrosa]

16Bit ADC

Yes, you will have to use a separate device. The resolution on the microcontroller is limited by the noise generated by the microcontroller during normal operation. At least one of the midrange PICs have a 12bit ADC inside, but only 10 bits are valid. I saw a preliminary release on a chip a few years ago.

To get a good reading with a 16 bit ADC, you need to pay close attention to board layout (like Beowolf said). You may also want a dedicated voltage regulator and some isolation in the communication to the PIC.

There are ADCs available that use serial communication like SPI and I2C.

**broken link removed**

**broken link removed**

http://focus.ti.com/paramsearch/docs/parametricsearch.tsp?family=analog&familyId=390&uiTemplateId=NODE_STRY_PGE_T&virtualTreeURL=D_PARAMETER_2000084|EQ|16

 

[un-2000]

Re: 16Bit ADC

used analog device chips and samples free for 16 to 24 to 48 bits
for serial interfaz