Build your first circuit
A DC source and a resistor, wired up and simulated, from an empty canvas in about five minutes.
Britt Espinosa
Last Update 15 дней назад
This builds a 5 V source across a 1 kΩ resistor, with a ground. By the end you will have run an analysis and read a number off it.
Open a new circuit
From the left navigation choose Circuits, then New circuit. An empty canvas opens with the Schematic panel showing and the Components drawer down the left side.
Place the parts
The fastest way to place a part is Quick Search. Click the canvas so it has focus, then press Ctrl+Space. Type a short code and press Enter:
| Type this | You get |
|---|---|
| dc | DC Voltage source |
| r | Resistor |
| g | Ground |
Place the DC source on the left of the canvas, the resistor to its right, and the ground below the source.
You can also find each part in the Components drawer and click it, then click the canvas. The hint at the bottom of that drawer reads Click to place · drag to canvas, and both work.
Wire them together
Press W for the wire tool, or pick Wire tool from the panel toolbar. Click the pin at the top of the source, then click the pin at the top of the resistor. A wire follows the grid between them.
Do the same along the bottom: source to resistor, and then a short wire from that bottom connection down to the ground symbol.
Every circuit needs a ground. Without a 0 V reference the simulator has nothing to measure voltages against, and the run fails.
Set the values
Press S for the select tool and click the resistor. The Item Properties panel on the right shows its settings. Set the resistance to 1k.
Click the source and set its voltage to 5.
Units follow SPICE conventions, so 1k is a thousand ohms and 1meg is a million. Be careful with 1m, which is a thousandth rather than a million.
Run it
Choose DC Operating Point in Simulation Type on the right, then press the run button in the top bar. The status beside the circuit name moves from Ready to a progress percentage and back.
Turn on the Table panel from the row of section buttons at the top. The node voltages and the current through the resistor are listed there. With 5 V across 1 kΩ you should see 5 mA.
Save it
Press Ctrl+S, or use the save button in the top bar. CircuitSim does not save on its own.
Click the circuit name at the top left to rename it from the default.
What to try next
Change the resistor to 2k and run again. The current should halve.
Then swap Simulation Type to Transient and add a capacitor to watch something change over time. Which simulation type do I need? covers what each analysis is for.