Question

What does a pmic do?

Answer 1

Answer:

There are PMIC devices which are preset with the relative timing and relationship among the various rails, with some flexibility. Other are more fully user programmable, often via an I2C or PMBus interface, to allow the user to set the specifics of the sequencing and other parameters that the PMIC is managing. In some cases, a few external cents such as resistors or capacitors may be needed by the PMIC. In very complicated systems, a dedicated microcontroller may be used with the sole task of providing PMIC functions.

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