PD interface

PM8803

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Doc ID 018559 Rev 2

4.7

5 V bias regulator

The PM8803 features an accurate 5 V output regulator, which can be used to bias the

DC/DC feedback network and the optocoupler connected to the microcontroller.

A capacitor in the range of 100 nF - 2.2 µF must be connected to ARTN for stability.

The regulator current is supplied from the VC pin, to take advantage of the more efficient

bias from the auxiliary winding. This means that the current drawn from the VB pin must be

taken into account to evaluate the maximum current drawn from the VC pin

The current drawn from the VB pin must be limited to 10 mA maximum.

The VB regulator is also able to accept injected current up to 1 mA without losing voltage

regulation.