SaM - Sigma-Delta Converter (AD Converter)

Remeber:

• This is the structure of the Sigma-Delta Converter:
  
• ==For this converter you need a not-referenced capacitive sensor==.
• Understand How Sigma-Delta Converter Works, here is a simpler formula, to remeber, to understand how it works:$V_{out}=V_{ref}\cdot \frac{\text{\# of 1s}}{\text{\# of 1s}+\text{\# of 0s}}$

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Memory Card

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• ==You have a no referenced sensors==

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Understand How Sigma-Delta Converter Works:

From Online Resource: Youtube

• $u$ : paid amount each day (etiher $5€$ or $0€$)
• $y$ : is the average paid over $n$ days.
• $x$ : is the fixed price of the coffee.

• So $x$ is the input
• $u$ the fixed amount passed to the comparitor (either $V_{REF}$ or $0V$)
• $y$ the “running average”, it’s possible to average
• You can get the exact value of $x$ of the coffee only by averaging many samples.
• Here, what happens is that the $1$ bit, A/D, at the end, outputs a $0,1,0,1,1,\dots$, sequence whose average value:$V_{out}=V_{ref}\cdot \frac{\text{\# of 1s}}{\text{\# of 1s}+\text{\# of 0s}}$ is actually the analog voltage input $V_x$, so $V_{o}ut\simeq V_x$.
• The precision of the average is decided by how many bits I use to sample a single signal $V_x$.

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