I have two questions about the INA827 and two pieces of information for TI related to apparent errors on the part's data sheet (SBOS631B-JUNE 2012-REVISED NOVEMBER 2017).
1st Question:
I am interested in uses of this part immediately (within tenths of a second) after it is powered, but I only found one relevant piece of information; a graph (Figure 53) on its data sheet which shows that it takes roughly 2 minutes for its offset voltage to drop from a few microvolts to its nominal value. In the application I have in mind, I do not care if the offset voltage is even a hundred microvolts away from nominal during this period. What I would like to know is in general how quickly the INA827 can be reasonably used after it is powered (from a single 5V supply). For example, what, if any, important characteristics of the device are seriously degraded if it has only been powered one, two, or three tenths of a second before its output is sampled?
2nd Question:
Another graph on the data sheet (Figure 52) indicates the INA827's "open-loop"output impedance is extraordinarily high at very low frequencies (in the mHz range). First of all, it appears that none of the three amplifiers within the IC (A1, A2, and A3 as shown in its "Simplified Schematic") are operating in an open-loop mode; they all have feedback. So, perhaps the reference to "open-loop" in Figure 52 is just indicating that this graph of output impedance is for a circumstance in which there is no external feedback around the IC. If that is the case, however, its megohms of output impedance at very low frequencies would appear to rule out the INA827 for many applications it otherwise might have fit excellently. Any clarifications you can provide related to all this would be appreciated.
1st Piece of Information for TI:
It appears that some TI reviewer's comments regarding the INA827's data sheet have accidentally been left in section 7.1 (Overview) in the data sheet.
2nd Piece of Information for TI:
The subheading for the last column of the "Table 2. Error Calculation" is "G = 1 ERROR (ppm)," but the INA827 does not appear to have a G = 1 option. Looking at the paragraph just above the table suggests that one of the last two columns (I am not certain which) is for G = 10 and the other is for G = 5.
