The MPSA42-D26Z is a small signal NPN transistor from ON Semiconductor. This device is a general purpose transistors with a maximum current rating of 500mA and a maximum voltage rating of 30V. This transistor can be used for switching and amplification applications. It features an NPN bipolar construction and a TO-92 package, which makes it ideal for use in space-restricted designs. This transistor is suitable for applications including signal amplifiers, digital logic drivers, and small relay or signal switching.