(Urgent)PSRR of Banba Bandgap circuit

[MichaelHelal]

I have a problem on PSRR value. it should >= 50 db.

how to improve PSRR of circuit known that supply voltage is low " 1.1 V"

Note: I tried to: 1) increase length and width of current mirrors PMOS transistors and results in random variation for the PSRR.
2) i increased gain of OP amp (5T OTA) from 40 to 100 and it decreased unexpectedly.

Thanks in advance.

the circuit is below.

 

[frankrose]

Hi,

Try with ideal OTA to identify that how much is the achievable maximum PSRR (DC 50dB you need or at a certain frequency? over PVT corners you need it?), maybe your bandgap architecture is not capable for this.
Please share your testbench too, maybe it is only a simulation method issue.
And finally, please share OTA schematic with component sizes, annotation results and how you tried to increase gain, these are not obvious. To find a solution we have to see all.