I am working on a design that uses the PF8200. RESETB_MCU, INTB, PGOOD, and FSOB are all open drain signals that the datasheet recommends pulling up to VDDIO. However, for my application, I would like to pull them to a slightly different voltage. Since these are all open drain outputs, I believe this is acceptable, but I was hoping someone from NXP could provide a little more direction. Here are my questions:
1. Does the voltage on VDDIO affect how high I can pull the open drain outputs? For example, if VDDIO is 1.8V, can I pull the open drain outputs to 3.3V and still get proper operation?
2. If VDDIO is 3.3V, can I pull the open drain outputs to 1.8V and still have them work properly?