Archive for June, 2011

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Faith Is Necessary

June 15, 2011

This is a followup to a previous post, Faith is Irrational, where I show that Faith (the Christian definition of the word) is, well, irrational.  This post attempts to cover the other side of that coin to show why Faith is necessary.  Like the first post, keep in mind that I am not trying to change anyone’s religion.  Also, this post is 100% conjecture on my part and worth exactly what you’ve paid to read it.

Faith is the firm belief in something for which there is no proof.  Or at least, we have not personally been exposed to this proof.  This is completely irrational, yet we do it every day.  When we go to the Doctors office, we have faith in the treatments he gives despite not having first hand knowledge in how it works.  We drive through a green light without knowing that the cross traffic has seen the red light.  We eat food without knowing that it has been safely prepared.  Why is that? Read the rest of this entry ?

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ADC In An FPGA, Part 2

June 5, 2011

This is part 2 of “ADC In an FPGA”.  If you have not read part 1, here it is.

Part 1 covered an overview of the ADC design.  Part 2 is going to cover a small part of it, but in more detail.  Specifically, the math around the RC filter model and how to optimize it to almost nothing.

The RC filter model is basically a chunk of logic inside the FPGA that attempts to predict what the external RC filter is actually doing, without directly measuring it.  The math behind this is conceptually easy, so here’s the formula.

New_Voltage = Current_Voltage + (RC_Input_Voltage – Current_Voltage) * (1-exp(-T/RC)) Read the rest of this entry ?