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How to avoid floating nodes in PSpice?

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dkace

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pspice node is floating

I am trying to simulate a voltage doupler I found in Horowitz a voltage doupler - I also posted it as a reply in a request for doupling.
I found out that I couldn't simulate it because spice was seing all these nodes as floating.
Does anyone has this solution? How do you work around the floatting node problem? If I put a ground, the circuit doesn't work properly - ofcourse this is something we all expect-.
Thanks,
D.
 

pspice floating

You always need a reference point (node 0 or GND) and you can avoid floating nodes by connecting a very high resistor from the node to GND
 

pspice node floating

you should place a 10Meg resistence between that node and ground.
 

node is floating pspice

No good people! The circuit doesn't work again as it sees a path to ground ( I guess). I have 200mV outpout when I put a resistive load and 300mV without the load. Any other Idea? The whole problem is how to simulate an isolated ground. Has anyone met this before?
 

pspice node is floating error

Try 100G ohms. This is more in the surface leakage range and if your circuit does not work in simulation with this, it will not work in hardware.
 

pspice floating node

I tried 100G and generates a simulation error. I tried 10G and I don't have doubling of the output, still 300mv with ripple.
Now If I want it to have isolated power supply from this circuit, this means that I can't have any simulation data?
D.
 

pspice floating node error

Have you connected load to voltage dubler or you are simulated unloaded.
 

node gnd is floating

Yes I did ! I tried with load and without load. All the time the same; eiter I don't have doubled voltage, or I can't have it simulated. It's a spice glitch, I am sure of it but how can we solve it? Is anyone with spice programming knowledge around?
D.
 

pspice error node is floating

Hi,

A schematic is better that a lot of discussion. Post a drawing of your circuit and for sure people here will try to simulate it.

If you are using capacitors put a high resistor value (1E9 ohms) in parallel of each capacitor.

If you are using a transformer, put the same resitor value between primary and secondary windings.
 

pspice is floating

HI, instead of connecting resistance, if u using PSPICE capture, then there is a ground part in the source library. connect this and see..i got the same error once. i did this and it worked fine
abhi
 

pspice error node floating

I think U must U the GND or 0 because PSPICE wont do anything without them.
U can add a very high resistor to avoid the effect of GND.
 

floating nodes in pspice

Just reminded me of an incident - a friend was using R from some other library, PSPICE gives a warning of floating nodes. When i simulate the same design, this time using R from the library of Analog, it works just fine!
Check it out!
 

this error occurs when spice can't run a DC analysis on your circuit, meaning that all DC node voltages are zero in your circuit.
it does not matter what type of analysis you are doing (AC,DC,TRAN,..) . SPICE does a DC bias analysis before ANY type of analysis and if it fails to find the DC values of all nodes, it reports floating point nodes.
solution : place a DC current source (IDC) and a very large resistor (say 100MEG) in parallel with your AC source (say your IAC or VAC). this will set your DC bias voltages, but has almost no effect on your AC analysis.
 

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