Hi,
A bit of an odd question to put on this forum perhaps, but here goes.
I am learning about oscillators, in particular those driven by crystals. I have been reading a very useful article but have come unstuck with one of the formulas provided in the example and wondered if someone might be able to help me...either the article is wrong, or I am calculating it wrong. Here goes...
The formula for calculating the feedback resistor (Rs) is given as
Rs=1/2πƒC2
In the provided example, f=20MHz and C2=27pF, thus
Rs = 1/[(2π)(20MHz)(27pF)]
When I calculate this I get a value of around 294.6 ohms
i.e. 1/((22/7)*2*20000000*0.000000000027) = 294.6127946127946127946
whereas the author gets a value of 398ohms.
Can someone help explain where this difference might be coming from?
A bit of an odd question to put on this forum perhaps, but here goes.
I am learning about oscillators, in particular those driven by crystals. I have been reading a very useful article but have come unstuck with one of the formulas provided in the example and wondered if someone might be able to help me...either the article is wrong, or I am calculating it wrong. Here goes...
The formula for calculating the feedback resistor (Rs) is given as
Rs=1/2πƒC2
In the provided example, f=20MHz and C2=27pF, thus
Rs = 1/[(2π)(20MHz)(27pF)]
When I calculate this I get a value of around 294.6 ohms
i.e. 1/((22/7)*2*20000000*0.000000000027) = 294.6127946127946127946
whereas the author gets a value of 398ohms.
Can someone help explain where this difference might be coming from?
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