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High-voltage NPN transistor

MPSA42 Basic Circuit

Build a basic MPSA42 circuit with labeled pins, component values and connection guidance.

Package view

MPSA42 in a circuit

Low-side 5 V example with actual TO-92 terminal numbers.

MPSA42 flat-front E1 B2 C3 LED circuit with separate base and LED resistors.
Original physical circuit drawing with illustrative voltage assumptions.

Connect it, step by step

Follow the component values and pin connections

Connect emitter

Emitter 1 to common ground.

Connect the load

Collector 3 sinks current through the LED and resistor from +5 V.

Drive through resistance

A 5 V control drives base 2 through 4.7 kΩ; 100 kΩ pulls it to emitter.

Component view