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, 09-06-2026, 03:20 PM

Hi i was trying to make a cuiorcuit simulator type using 2 toggle switches which can get states of 12 v 9v 6 v 3.3v any recommenfation

, 09-06-2026, 03:23 PM

🤖 In the meantime, here’s a response from the [FEDEVEL AI HW Assistant]().
It helps to find relevant resources for your question, but it may make mistakes as it’s still in early development.

This is the response from the AI Assistant:
Here's how to approach creating a voltage selection circuit with 2 toggle switches for 12V, 9V, 6V, and 3.3V outputs:

**Basic Concept:**
Use a resistor ladder network where each switch combination selects different voltage division ratios. This requires:
1. A 12V power source
2. Two SPDT (Single Pole Double Throw) toggle switches
3. Precision resistors to create specific voltage divisions

**Recommended Circuit Configuration:**
```
12V Source
│
├─[R1]─┬─ Switch A ─┬─ Output
│ │ │
│ [R2] [R3]
│ │ │
├─[R4]─┴─ Switch B ─┴─ GND
```

**Design Approach:**
1. Calculate resistor values using voltage divider equations
2. Consider switch positions as binary inputs (00, 01, 10, 11)
3. Use simulation to verify voltages before building

**Simulation Recommendation:**
Use QUCS (Free circuit simulator shown in [this tutorial](https://www.youtube.com/watch?v=VBmuJfcMeFk&t=158)) to:
1. Model switch behavior (ideal or real-world)
2. Test different resistor combinations
3. Verify transient response and power dissipation

**Example Resistor Values (approximate):**
- R1 = 1kΩ
- R2 = 2.2kΩ
- R3 = 3.3kΩ
- R4 = 4.7kΩ

*Actual values need precise calculation using:*
`Vout = 12V * (Parallel Combination of Lower Resistors) / (Total Resistance)`

**Key Considerations:**
1. Add decoupling capacitors for stable voltages
2. Consider switch contact resistance (typically 10-100mΩ)
3. Use 1% tolerance resistors for better accuracy
4.

, 09-06-2026, 03:23 PM

Include overvoltage protection if powering sensitive circuits

For exact resistor values, use the voltage divider formula with your specific switch configuration, or use QUCS' parameter sweep feature shown in [this simulation example](https://www.youtube.com/watch?v=VBmuJfcMeFk&t=1608) to optimize your design.

You can continue chatting with the AI Assistant here:
https://fedevel.com/hw-assistant

QDrives , 09-07-2026, 01:57 PM

You should better explain what you want to simulate.

One simple thing you may want to look at is the ".step param Supply list 3.3 6 9 12" spice operation.
Then have the voltage source at "{Supply}" (note the curly brackets).