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Voltage division over reverse biased diode (pin-diode)

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Tybi

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Hello,
can someone tell me how the voltage splitts up in a network of reverse biased diodes? I have no idea how to solve this, because no current flows.
Here I have an example network.

1630585718975.png
 

Solution
G
For ideal diode the voltages between each diode are not defined, as barry said they are open circuit.
For any real diode, PINs included there will be a reverse leakage current, this will be modelled in you SPICE circuit models. A PIN diode SPICE model is much more complicated; the only ones I have seen are for use under restricted operating conditions as PSICE does not model the carrier life time in the I region. The manufacturers data sheet should give you the reverse leakage current under DC conditions, given that you can work out the equivalent resistance and the voltage across each diode.
This is only static DC, trying to work out the current for a PIN during the transition from forward to reverse bias can be tough.
It looks like...
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If these are ideal diodes, then they can be assumed to be open-circuits when reversed biased. The voltage doesn't "split up".

What are you trying to do?
 

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barry said:
If these are ideal diodes, then they can be assumed to be open-circuits when reversed biased. The voltage doesn't "split up".

What are you trying to do?
Click to expand...
Isn't it more like a capacitve voltage divider? In the RF-world pin diodes are used as switches.
 

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For ideal diode the voltages between each diode are not defined, as barry said they are open circuit.
For any real diode, PINs included there will be a reverse leakage current, this will be modelled in you SPICE circuit models. A PIN diode SPICE model is much more complicated; the only ones I have seen are for use under restricted operating conditions as PSICE does not model the carrier life time in the I region. The manufacturers data sheet should give you the reverse leakage current under DC conditions, given that you can work out the equivalent resistance and the voltage across each diode.
This is only static DC, trying to work out the current for a PIN during the transition from forward to reverse bias can be tough.
It looks like you are using LTSpice. The default diodes give a believable result for real life, half the total voltage across D3 and the res shared across the two pairs. Current in D3 is twice the current in each of the other pairs. Simple network theory treat the diodes as equal value high resistance resistors (in reality several Meg ohms). This ignores thermal and optical effects.
 

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Solution
Quite true, I was trying to keep it simple as OP says he has no idea how to solve it.
 

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