Increasing digital I/O pin current with MOSFET

An arrangement such as the below would be a typical approach. R1 selected as per this post, Q1 selected to have adequate voltage and current withstand ratings, while having sufficiently low gate voltage requirements as to be controllable from the available drive source. TN0702N3-G being a possibility.

Such approaches depend on regulation of the supply voltage to maintain consistent current flow. Where such regulation is unavailable, a current regulation IC such as a BCR421 can be used instead to improve regulation.

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