Grove I2C 12-Bit ADC, sampling rate

Hi,

http://www.seeedstudio.com/wiki/Grove_-_I2C_ADC

What is the actual sampling rate I could expect from this device?
The specs say 188.9ksps, but as far as I understand that's how fast the ADC is.
If i'm interested in continuous samples, i have to fetch them one after another.

I guess only a few samples per second are realistic?

I'd like to measure the RMS of a modulated DC voltage.

There is a big difference between 190ksps and a few samples per second. I would think that 10's of thousands of samples per second are possible, depending on what you do with the data,

What frequency of modulation are you expecting?
You’ll need to bump up the I2C speed to 400K from 100K default if you hope to achieve anything close to 190ksps.

What i ment is:

Would i have to send a 0x00 (REG_ADDR_RESULT) after every sample to get another one?
Or could i just keep reading (for example into an array).

I would need at least 200Hz sampling rate, the more the better of course.

I2C won't support fast conversion, its verbose and clocked slow. SPI every time for ADCs in my book.
That device might be able to get about as fast as analogRead() on the Uno if run at 400kHz, but thats
10kSPS, which is a lot more than "a few samples a second"!!

The 188kSPS is when run from 3.4MHz I2C, which the Arduino doesn't support (perhaps the Due does?)

I've the tiny little ACDS747X family before - nifty SPI converters, 8/10/12 bit versions and upto 1MSPS
with 20MHz SPI clock (ie upto about 250kSPS in practice with Arduino).

But back to the issue:

RMS of a signal - but you don't say what the bandwidth of the signal is... If its audio that's 20kHz so a
50kSPS rate or so is indicated. Or is it something slower?

So this:
Wire.write(REG_ADDR_RESULT);

From the sample code has just to be sent once, to tell the ADC what i want (Page 18 on the ADC specs)
and after I could keep reading byte after byte?

The signal to sample is only 50Hz.

It looks like the register address is sticky, so you only need to write it once. You can also read
continuously to get repeated samples from reg 0 (I'm pretty sure, though the datasheet doesn't outright
say this which is frustrating)

Ok, interesting.
Thanks.