Diode BehaviourThe exponential law, the 0.7 V model, and when each one is honest.Electrical EngineeringA diode conducts exponentially in forward bias andblocks almost everything in reverse.I = I_S (exp(V/nV_T) − 1) · V_T ≈ 25.9 mV at 300 KSilicon at 10 mA≈ 0.7 V forwardConstant drop.Schottky at 10 mA≈ 0.3 V forwardFaster too.Ten times the currentAbout 60 mV moreFor n ≈ 1.THE COMMON MISTAKE✗ Paralleling diodes to share a large current✓ Giving each one its own small series resistorThe exponential law means the diode with the lowest forward voltage takesnearly all the current and overheats first.Forward voltage falls roughly 2 mV per degree, so a hot diode conductsharder. That is the thermal runaway mechanism.Diode Behaviourlearnposters.com
Diode Behaviour — printable engineering wall chart from LearnPosters. Free vector PDF, US Letter and A4.

What’s on the Diode Behaviour poster

The rule, 3 worked examples, and the mistake everyone makes.

Forward voltage falls roughly 2 mV per degree, so a hot diode conducts harder. That is the thermal runaway mechanism.

Questions about the Diode Behaviour poster

What’s on the Diode Behaviour poster?
The rule, 3 worked examples, and the mistake everyone makes. A diode conducts exponentially in forward bias and blocks almost everything in reverse.; I = I_S (exp(V/nV_T) − 1) · V_T ≈ 25.9 mV at 300 K; Silicon at 10 mA = ≈ 0.7 V forward; Schottky at 10 mA = ≈ 0.3 V forward; Ten times the current = About 60 mV more; Common mistake: Paralleling diodes to share a large current → Giving each one its own…. Forward voltage falls roughly 2 mV per degree, so a hot diode conducts harder. That is the thermal runaway mechanism.
Who is the Diode Behaviour poster for?
Diode Behaviour belongs to the Electrical Engineering section rather than to a school year, because engineering is not something one grade owns. Anyone learning electronics can pin it up — a beginner, a student mid-course, or someone revising years later.
When should you use the Diode Behaviour poster?
Pick the simplest model that answers the question, then test it against the next one up. A wall chart earns its place by being glanceable from where the work is happening, so Diode Behaviour belongs on the wall where that engineering work actually happens, within glancing distance, rather than filed away.
What other posters go with Diode Behaviour?
BJT Operating Regions, BJT vs MOSFET and Common-Emitter Amp sit alongside Diode Behaviour in the Electrical Engineering section. Printed together they make a wall rather than a single sheet, which is how a reference set actually gets used.BJT Operating RegionsBJT vs MOSFETCommon-Emitter Amp
Is the Diode Behaviour poster free to download and print?
Yes. Diode Behaviour downloads as a free PDF with no account, no email and no watermark, like everything else in the Electrical Engineering section. Print as many copies as you like for a home, a classroom, a library or a tutoring group; reselling the file is the only thing the licence rules out.Read the licence
What size does the Diode Behaviour poster print at?
Diode Behaviour is a vector PDF laid out for US Letter, and prints on A4 with Fit to page — the same file, no separate download. Because every mark on it is drawn rather than photographed, it stays sharp enlarged to A3, A2 or A1 at a copy shop. Colour carries emphasis only, so a greyscale print of Diode Behaviour loses nothing.Printing guide

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