FAQ

Q 

There is an information in AD7794 Data Sheet: RMS noise: 80 nV (Gain = 64). And
there is an information in Product Description and presentation about AD779x:
40 nV (Gain = 64). What is true?

A 

The rms noise is 80nV when the gain equals 64 and the…

Q 

I'm interested in additional register information to the configuration register
of the AD7194. It has 3 Gain bits to select the ADC input range. Is it possible
to also use Gain 2 or 4 (I assume a value of 1 or 2 to write to the gain bits).

Q 

I have a question regarding the AD7794 datasheet. On page 23 there is a table
of channel select bits. For an input of 1000, the channel is states as
AIN1(-)/AIN1(-). This will always be zero, so I wondered whether it is correct,
or whether it…

Q 

In Evaluation Board for the AD7794 (24-Bit, 6 Channels), when I use the AD PC
software, what is upper limitation of sample size, that has to be entered in
the "Num Samples" text box?

A 

The software can gather up to 65000 samples.

Q 

I've got the latest datasheet but there are still two unresolved problems:
question 1:
page 5 says, NOXREF is active when Vref is less than 0.3 V but page 20 tells me
0.5 V. What is the real low limit for missing reference detection ?

question…

Q 

I am using the EVAL-AD7794/95EB board, and I can't setup a SPI communication
with using an STR9-EVAL board , I am using the external power supply (5V) LED
is ON (D1 is on when USB connected), I would like to know if ADC's SPI can be
used…