NPN
NPN bipolar transistor
A bipolar transistor with base, collector and emitter terminals arranged for NPN operation.
Schematic
Symbols · PNP
PNP bipolar transistor
A bipolar transistor with base, collector and emitter terminals arranged for PNP operation.
Schematic · PNP
What it represents
A bipolar transistor with base, collector and emitter terminals arranged for PNP operation.
On a schematic, identify the base drive and emitter supply/reference and trace the collector load and switching or amplification path. Keep the component tag and signal/reference names consistent across the control drawing, terminal schedule and device documentation.
PNP polarity differs from NPN; mirrored graphics do not change a transistor's type or package pin assignment.
Terminal letters describe electrical roles, not package pin numbers. Check the selected public datasheet for the actual pin assignment, polarity and any internally connected terminals before completing the drawing.
How to read it
- Identify the base drive and emitter supply/reference.
- Trace the collector load and switching or amplification path.
Information to show or reference
- Label the base drive and emitter supply/reference.
- Cross-reference the collector load and switching or amplification path.
- Add the selected device or circuit documentation revision, power/reference connections and project signal convention.
A distinction that matters
PNP polarity differs from NPN; mirrored graphics do not change a transistor's type or package pin assignment.
Sources you can follow
These public references support the explanation and provide further detail. Their graphics and downloadable files remain with their publishers.
BC856/BC857/BC858 PNP transistor documentation
Public primary manufacturer documentation establishes the component function or circuit/topology relationship. Preview geometry and drafting explanations are independently authored.
About this graphic
This illustration was authored independently by Elora Grid to explain the concept. It is not reproduced from a customer drawing, an official standard graphic or a manufacturer CAD file. Its correspondence to an exact IEC or IEEE symbol identifier has not been certified.
SVG and DXF downloads contain this original artwork. DXF uses unscaled drawing units; a GA envelope supplies no product dimensions, clearances or fabrication information. Original artwork is available under CC BY 4.0. Third-party references retain their own terms.
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