Bridge rectifier transfer function

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The discussion focuses on identifying the correct transfer function for a bridge rectifier. The output voltage of a rectifier remains above or below the x-axis, and output occurs only when sufficient voltage activates two diodes in the bridge. The transfer function could be either (b) or (g), with (g) being preferred for a positive output. Participants clarify that the graphs depict the relationship between input and output voltages, emphasizing the need to consider diode configurations. Overall, the conversation enhances understanding of rectifier behavior and transfer functions.
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Homework Statement


I am asked to decide which one of these is the transfer function of a bridge rectifier
upload_2017-4-12_21-46-9.png

I was thinking D, but my friend says D is for when there is only one diode. Can anyone explain what the right choice is and why? This is not homework, rather preparation for my final.
 
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You'll need to provide an attempt at solution along with your reasoning for that choice. What exactly are the graphs showing?
 
gneill said:
You'll need to provide an attempt at solution along with your reasoning for that choice. What exactly are the graphs showing?
Well they show vout along the x-axis and vin along the y-axis. I suppose it would make sense for D to be for one diode, since it would only start conducting at 0.7, and after I assume the slope is 1 ?
 
I assume the horizontal axis is a floating differential voltage input, and the vertical axis is the resulting floating differential output voltage while some current is being drawn by a load.

For a rectifier the output voltage will always remain above or below the x-axis.
There will be no output until there is sufficient voltage to turn on two diodes in the bridge.

The output transfer function could be (b) or (g) depending on the polarity of the output.
I would nominate (g) as it is a positive output.Half of the figures are simple cases of reversing the input or output polarity convention. Apart from the bridge, there are forward and reversed diodes. There is also a pair of back to back diodes in parallel.

Now you should be able to go through the figures and draw a circuit using one, two or four diodes that will give each of those transfer functions.
 
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Baluncore said:
I assume the horizontal axis is a floating differential voltage input, and the vertical axis is the resulting floating differential output voltage while some current is being drawn by a load.

For a rectifier the output voltage will always remain above or below the x-axis.
There will be no output until there is sufficient voltage to turn on two diodes in the bridge.

The output transfer function could be (b) or (g) depending on the polarity of the output.
I would nominate (g) as it is a positive output.Half of the figures are simple cases of reversing the input or output polarity convention. Apart from the bridge, there are forward and reversed diodes. There is also a pair of back to back diodes in parallel.

Now you should be able to go through the figures and draw a circuit using one, two or four diodes that will give each of those transfer functions.
Thank you, this is really clear now!
 
The book claims the answer is that all the magnitudes are the same because "the gravitational force on the penguin is the same". I'm having trouble understanding this. I thought the buoyant force was equal to the weight of the fluid displaced. Weight depends on mass which depends on density. Therefore, due to the differing densities the buoyant force will be different in each case? Is this incorrect?

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