Other Parts Discussed in Thread: BQ25730,
BQ25730 and BQ25731 are buck-boost charge controllers, with same package, same pinout and similar functions. BQ25731 is specially designed for non-power-path applications. No battery MOSFET (BATFET) saves cost and increases efficiency.
Although both parts are similar in functions, there are a few register setting differences, for example the EN_LDO mode and default charge current for auto wakeup. Moreover, the BQ25731 is specially designed to handle the startup without BATFET. Therefore, we do not recommend to replace BQ25731 with BQ25730. They are not interchangeable parts.