Part Number:LM27762
Hello,
I noticed in this E2E post that the overall dropout for the negative output must be the sum of the LDO dropout and the charge pump voltage drop: https://e2e.ti.com/support/power-management/f/196/t/659023
Looking at Figure 4 of the datasheet, I see that at 1mA of load current the CP resistance could be as high as 300-Ohm. That would result in a 300mV drop. Does that mean for a -5V output, the input voltage would have to be 5V + 300mV =5.3V? (at very lower current the LDO dropout appears to be negligible)
In this application we have 6Vin, but I want to use the LM27762 to generate +/-5V. Since the max input voltage is 5.5V, I'm thinking of using a very low dropout LDO to step down the 6Vin to a safe intermediate voltage.
I don't want to get too close to the maximum of 5.5V, but is 5.4V my best bet? Could the negative dropout get even greater than 300mV under a no-load condition (<1mA)?
Thank you!
Regards,
Ryan B.