adc-i2c for xm a3

  I would like to know how to interface an adc-i2c chip onto
beagleboard xm a3.
we are basically looking at 3 options for the adc:
1)ads7828 ic
2)ads7828 evaluation module
3)an adc manufactured by which is based on ads7828.
we would like you to suggest which would be a better option.we would
also need guidance on the type of buffer op-amp circuit we would need
to collect the signals for the adc.

Connect it to teh I2C pins on the expansion connector. You may need to level shift it depending on the voltage the devices you choose to connect are running at. The voltage level on the expansion header is 1.8V.

As to the buffer or OPAMP that depends on what voltages and frequencies you plan to connect to ans whether or not gain is needed… It is not clear to me you even need it, but then again I have no information at all as to the issue your defined solution is intended to solve.


Thank you for the reply Gerald.
Our project is about building an oscilloscope on the android platform
which will be ported on to the beagleboard xm a3.The ADC should
communicate with the beagleboard using the i2c interface.For this we
want to know whether the ads7828 ic or the ads7828 with evaluation
module would be a better option.What exactly is the difference between
the two?
Thanks & Regards,

If you use the evaluation board, there would be less work from a hardware perspective. It has he part mounted on a PCB wih connection points to connect incoming signals and to connect it to the BeagleBoard.I would go that way.


In message

@Gerald:Thanks for the reply.We will now consider using ADS7828 with
Evm.We will look at designing a suitable input buffer circuit for
it.If you have any suggestions,please post it

@Dave:Yes Dave,ours is just an academic project for our final year.We
have to design it within a short period of time.So it wont exactly be
a software oscilloscope in the true sense.