Hello, we are using the TPS62175 as an inverting power supply. We are using it in two configurations. One of the configurations is working and the other is not.
Below is a configuration that is working. That is:
VIN = 12V
Expected Output = -2.0V
We are reaching ~-1.995 volts with this R1 / R2 configuration with no issues, The voltage output stays steady with or without a load. This configuration is working nicely.
We are trying to use this same configuration, and only changing the value of R1 / R2 to try and achieve a -3.3V output but we cannot seem to get it to work.
Below are the different R1 / R2 configurations we are trying for an inverted output of -3.3V. Both configurations result in a Voltage starting at -3.0V and as the device is powered over time, the voltage output changes to -2.6 and then stays there.
Attempted Resistor R1 / R2 Configurations for output of -3.3V
We have double checked the calculations for the -3.3V output as well as the -2.0V output, why would this work at -2V and not -3.3V?