Circuit Block Diagram Visualizer
Probe a microcontroller power and signal chain with a virtual oscilloscope
How to Use This Tool
This interactive visualizer models a typical microcontroller power and signal distribution circuit. Use it to explore how each stage works, probe signals with a virtual oscilloscope, and simulate common hardware faults.
Explore the Schematic: Click any circuit block (Power Input, V-REG, MCU, Oscillator, Output Stage) to inspect its operating parameters, key components, and recommended diagnostic tools in the side panel.
Probe with the Oscilloscope: Click a Test Point (TP1–TP5) on the schematic to connect the virtual probe. The oscilloscope canvas below will render a live animated waveform for that signal. Use the Volts/Div and Time/Div sliders to zoom in/out, and the Hold button to freeze the display.
Simulate Faults: Toggle the Fault Simulation switch, then select a fault scenario from the dropdown. The affected block turns red, downstream signals distort or flatline on the scope, and a diagnostic drawer appears with observed symptoms, step-by-step test procedures, and suspect components for replacement.
Signal Flow Schematic
Virtual Oscilloscope
Block Inspector
Fault Finding by Signal Chain
Nearly every embedded board, however complex it looks, reduces to the same chain: power comes in and is protected, a regulator turns it into a clean rail, that rail feeds a microcontroller, an oscillator gives the controller a clock, and an output stage drives whatever the board exists to drive. Diagnosing in that order matters, because a fault at any stage produces convincing symptoms in every stage downstream of it. A dead output is far more often a regulator or clock problem than a dead driver.
Work from the supply inwards
Confirm the input rail before you probe anything clever. If the protection diode is shorted or the fuse has gone, everything past it reads as dead and no amount of MCU probing helps. Once the raw input is good, check the regulated rail under load rather than open circuit — a marginal regulator often holds voltage with nothing attached and collapses the moment the controller starts drawing current. Only when the rails are proven does it make sense to look for a clock.
What each simulated fault teaches
The four scenarios here mirror the failures that actually turn up on the bench. A blown input fuse or shorted protection diode gives a completely flat board with no rail at all. A leaky filter capacitor leaves the rail present but riding on heavy ripple, which shows as random resets and glitching rather than a clean failure — this is the one people misdiagnose most, because a multimeter’s averaged DC reading looks acceptable while the scope shows the truth. A failed crystal oscillator leaves the rails perfect and the controller silent, since without a clock nothing executes. An open MOSFET or driver stage gives a board that boots, communicates and reports itself healthy while driving nothing.
Test-point discipline
Probe at defined points and note what you measured, not just whether it looked right. Ripple, rise time and duty cycle are the properties that distinguish a healthy rail or clock from a marginal one, and none of them show on a multimeter. Ground your scope probe as close to the block under test as you can — a long ground lead invents noise that will send you chasing a fault that is not there.
For the numbers behind the stages, the Ohm’s law calculator sizes dissipation and the 555 and LED calculator covers timing and drive current.