How to create bipolar power supplying from Powerbank 5V 3A
If your goal is bipolar operation as shown in figure 54, then there might be a problem.  Sticking with TI parts, they make a &quot;virtual ground&quot; chip that will take in a 5 V supply and split it into +/-2.5 V rails by creating a virtual ground at 50% of the input voltage.  But ...
The problem is that now the maximum positive rail with respect to power and system ground is +2.5 V, and you might need +3.3 V to assure a high enough output voltage to be seen as a logic 1 reliably.
Separate from that, other system components still be referenced to the power supply GND which is the -2.5 V rail to the ADC.
If either of those is an issue, then a charge pump circuit mentioned above might be needed.