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DPDT Center-Off: Two Supplies, One Control

CI

CircuitSim

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Created Oct 20, 2026

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Updated Oct 20, 2026

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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
NameManufacturerMPNCountType

Resistor

Generic

—

4

Official

DC Voltage Source

Generic

—

2

Official

Switch - DPDT

Generic

—

1

Official

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