# Ratio between voltage input to output in dc-dc conevrter (FS20-12)

In the datasheet of product having model number FS20-12 it is written that output voltage is proportional to input voltage and the range of input voltage is from 0.7 to 12V. I want to know the output of the product at the input values of 0. to 12V. For example at input of 5V what will be the output or at input of 10V or 11V, what will be the output. In short, I want to know the ratio between output voltage to input voltage of this particular product.

Welcome to the forum.

Data sheet says at full input and load, output = 2000V, so the transfer function should be:
Vout = Vin * 2000/12 = Vin * 166.7

Since the Vin range is 0.7V to 12V, the transfer function is not valid below 0.7V.

Page 6 of the data sheet has a graph that shows the limitations and non-linearities.

From the graph, below 0.7V input the output falls off rapidly to 0V. It also shows that below full load (5mA) the transfer function is very non-linear and reaches 2800Vout with 12Vin @ 0mA.

So the Vout for your example Vin points with a 5mA constant current load:
5V = 833.3V
10V = 1666.7V
11V = 1833.3V

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