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I usually find relay circuits using NPN transistors to drive it on/off. This one has a PNP, will this relay circuit work? What's the difference?

It's a BC858B.

enter image description here

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Looks perfectly OK. You pull the input line low to turn on Q5, which saturates on and turns on both the LED and the 5V relay. It's just upside down to the usual way of doing things.

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    \$\begingroup\$ @AminMansouri R14 is somewhat critical... If this is substantially lower than the relay resistance, the relay might not turn on. \$\endgroup\$
    – tobalt
    Commented Jun 3, 2021 at 12:47

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