DPDT Center-Off: Two Supplies, One Control
CircuitSim
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Created Oct 20, 2026
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Updated Oct 20, 2026
Details
Components
3
Schematic
Yes
Simulation
Interactive
Copies
Not copied yet
About this circuit
Switch 5 V and 3.3 V supplies together between their NC and NO loads, or disconnect both poles in the center.
Circuit notes
DPDT Center-Off: Two Supplies, One Control
Switch 5 V and 3.3 V supplies together between their NC and NO loads, or disconnect both poles in the center.
Try it
Click SW1 to cycle from center off to NO, then NC, then center off. To try spring return, change SW1’s Operating mode to Center-off momentary. Hold the upper throw for NC or the lower throw for NO; release to return to center. The two-position Latching and Momentary options remain available.
Expected behavior
All outputs start near 0 V in the center. Selecting a throw raises its loaded outputs to approximately 5 V for pole A and 3.3 V for pole B. The dashed link represents shared mechanical motion; the poles are electrically isolated. Inactive outputs remain near 0 V. Each 1 kΩ load draws about 5 mA on a 5 V rail or 3.3 mA on a 3.3 V rail.
How it works
The voltage probes measure the outputs relative to the common supply return. Probe colors match the chart traces. These idealized contacts change without bounce or transfer delay. Closed contacts use a small finite resistance; open contacts use a large finite resistance to keep the live simulation stable.
Components used
Components used
3 components
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