Know what the model can show.
NPNLab is a browser learning workspace for reasoning about circuits—not a promise that every visible part behaves like physical hardware.
Start with a bounded example
Use a simple resistor loop, a current-limited LED and switch, or an unloaded resistor divider to practice predicting and inspecting supported observations. Public worked examples explain the intended nodes and assumptions; they do not silently import a design or certify real hardware.
Examples and boundaries
| Area | Learning use | Important boundary |
|---|---|---|
| Circuit workspace | Place components, draw wires and arrange a circuit. | Visual placement and electrical behavior are separate; use supported parts and connections. |
| Resistor and LED circuits | Explore simple DC resistor networks and current-limited LED examples. | Bounded teaching models do not replace datasheets or represent every nonlinear or thermal effect. |
| Breadboard and reference nodes | Reason about modeled strips, shared connections and GND references. | An illustration or model cannot verify a physical board’s rail breaks, contacts or protective-earth wiring. |
| Switches and inputs | Investigate a series switch or a defined input level in supported circuits. | Do not assume a model reproduces mechanical bounce, leakage and timing for a real part. |
| Instruments | Inspect supported simulated voltage, current and signal observations. | Readings depend on supported topology and instrument access. A missing or unsupported observation is not zero. |
| Charge, energy and timing | Use the public guides for capacitor arithmetic and the limits of ideal models. | A worked formula is not evidence that an arbitrary dynamic circuit is supported by the Lab. |
| Firmware workflows | Selected board profiles and firmware features have model-specific support. | Board, peripheral and compilation requirements vary. No universal MCU support or public compilation entitlement is promised here. |
Access follows the platform
Public guides and calculators are readable without registration. Guided practice, persistent learning progress and some platform features require an account or additional access. Follow the platform’s actual access controls.
These public pages do not offer a paid-plan entitlement, change progression or bypass sign-in. Use the actual Lab to see available controls and supported observations for your session.
What this is not
- Not a general-purpose SPICE, PCB design or safety-certified engineering tool.
- A visible catalog part does not imply a complete electrical model.
- Simulated values are not physical hardware measurements; tolerances, thermal effects and ratings need independent verification.
- Do not assume general transient behavior, contact bounce or every microcontroller/peripheral is modeled.
For physical work, stay within appropriate isolated low-voltage experiments and verify component ratings, actual wiring and meter setup. An error-free calculation is not a hardware safety review.
How these public resources work
The guides are static educational explanations. The calculators perform bounded arithmetic in your browser without submitting the entered values to a server. Read our editorial method for their source and review limits.