adc CS5460A

ya i m sure that the input s varying.i displayed the output in the seven segment led.

ya i m sure that the input s varying.i displayed the output in the seven segment led.

Without providing good information, you cannot hope to get good answers!

Don't try to abbreviate everything (especially with SMS-style abbreviations) - give clear and complete explanations.

"ya i m sure that the input is varying."

How are you sure?

"i displayed the output in the seven segment led."

What output?

What 7-segment LED??

Hi

Sorry for sending like that.

I am using cs5460a as a adc in my project.My project is weighing machine.If i put any load,the adc has to sense that variable value,and to give the digital value to the 8051 microcontroller.

As a display unit,i have used seven segment led, it displays the corresponding load value.

This is the core of my project.

My doubt is whether i can use cs5460a as a adc(inbuilt of SPI).

I tried by writing code,but in the seven segment led,i am not geeting the proper output.

I have the doubt in the register configuration of cs5460a.I most of the sites,they displayed cs5460a is used as a power meter.whether i can used it as a adc.
Kindly reply me.

Sakthi

"I am using cs5460a as a adc in my project.My project is weighing machine. [...] I most of the sites,they displayed cs5460a is used as a power meter."

Have you read the datasheet for the CS5460A(www.cirrus.com/.../CS5460A_F2.pdf)?

This chip is a 'Single-Phase Bidirectional Power/Energy IC'. It is NOT a load cell ADC.

There are other Cirrus Logic ADCs that are specifically targeted for load cell applications, search from the root site above.

And yes, you potentially could throw away 90% of the CS5460A functionality and use it as an ADC, if you know what you are doing (but if you really knew, you wouldn't).

For that, you would have to select one of the 2 ADC inputs to use, and read its instantaneous or RMS value registers (V, Vrms, I, Irms). There are a few disadvantages in doing so:

* The analog full scale of the inputs is 100mv(min), too high for a standard 2mV/V load cell. That means that the effective number of signal bits will be lower than optimum;
* The Vref input is not true differential. That makes it difficult to make true ratiometric measurements, something essential in load-cell applications;
* You have to perform special calibrations amd conversion cycles having in mind that your signal is not a AC power line, but a DC source.

And of course, there is much much more to a weighing machine than read the ADC and display the results. First of all, your readings will whip like crazy. To get any usable readings you have to apply some serious filtering in your ADC data stream. It would be interesting to see what the hardware RMS signal filter can do for you in this regard...

Or maybe just plain barking?

The Datasheet clearly tells you that this is a 'Single-Phase Bidirectional Power/Energy IC';

This has been also pointed out to you in your cross-post at 8052.com: "?!

You need to go back to basics, start from your system requirements, and work from there - see: www.8052.com/.../read.phtml

hi jonny sir i read the datasheet from the same link,what you have attached.

my problem is in coding.that is intialization of the registers in cs5460a.i used spi communication between 8051 and cs5460a.

I configured the required register of adc cs5460a for adc conversion.With or without load the same value is displayed in the seven segment led.

"my problem is in coding."

Are you sure?

You have already been told by two independent observers that the cs5460a seems like a very odd choice for this project.

" href= "http://www.8052.com/forum/read.phtml?id=134721">www.8052.com/.../read.phtml

Again, why do you think that the cs5460a is suitable for this project?

"With or without load the same value is displayed"

Couldn't that just be because the cs5460a is simply not able to measure the change resulting from this load?

"You have already been told by two independent observers that the cs5460a seems like a very odd choice for this project."

Now it's three:

www.8052.com/.../read.phtml