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Why a series resistor on VDD line is needed for SPOC+2 devices?

Why a series resistor on VDD line is needed for SPOC+2 devices?

IFX_Publisher1
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There are three main reasons for putting a VDD resistor in the VDD line:

1) When the system is reverse supplied, there will be a current flow from microcontroller into VDD pin of the device. To stay within the maximum ratings, a series resistor has to be placed.

2) Transients on the battery could cause a positive or negative ground shift, which leads to a current flow through VDD pin. To limit the current during this application condition, a series resistor is recommended.

3) A series resistor will protect the digital supply in case of a fault condition at VDD pin when shared with other devices. Examples for fault conditions are external short circuit to ground on VDD pin or internal faults which lead to a high current consumption on VDD.

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