TPS7A8101: Please help me to see if there is any disadvantage in the design of TPS7A8101.

Hello Elsa,

The TPS7A8101 does not require a Cff capacitor to maintain stability.
Using a Cff capacitor will improve the noise performance of the linear regulator.
You can see the improvement with 2 different values of cap in figure 21 of the datasheet (copied below).

We typically recommend against resistor values in the 100's of kΩ due to the interaction from the feedback pin current.
The datasheet specifies this current as up to 1uA.
This current will flow through the feedback path and cause the setpoint to offset from what you would normally expect.
If you need help designing the setpoint, let me know and I can run a statistical analysis for you.
If so, I need the output voltage and tolerance that you need, as well as what resistor tolerances you wish to use in the design.

I see you have a zero ohm resistor in series with the output to the load circuitry.
Zero ohm resistors typically have a maximum resistance listed in their datasheets, which is commonly 20mΩ, but you should check your resistor to confirm.
If the load current will be large, you will want to be sure that the zero ohm resistor (which is not actually 0Ω but closer to 10m-20mΩ) will not adversely affect the output voltage.  For instance, if the load is 500mA and the zero ohm resistor is 10mΩ, you will see a 5mV drop in just the resistor alone.  This does not include PCB trace loss, or other losses (such as downstream inductors, ferrite beads, etc).  These milivolts can add up and cause a noticeable deviation in expected output voltage.

Thanks,

- Stephen