MMBT3904
by ST(先科)
MMBT3904 is a general-purpose NPN bipolar transistor commonly used for small-signal switching and amplification. It fits applications such as signal inversion, discrete transistor stages, and control circuitry. The supplied record identifies the manufacturer as ST(先科) and the package as surface-mount SOT-23-3. For KiCad, the free download pairs a 3-pin symbol with the 3-pad SOT-23-3_L2.9-W1.3-P1.90-LS2.4-BR footprint and includes a 3D model. That exact footprint name identifies the physical library variant supplied here. In real designs, 2 ProtoFlow engineers have used this conversion. The transistor's library files can be opened directly in ProtoFlow.
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