Which type of voltage divider is better?

[tomph]

Voltage divider question

1) V1 ------------||------Vdiv------||-----------|GND


2) V1-----------\/\/\/\----Vdiv------\/\/\/\/\-------|GND


The circuits above served as the voltage dividers . Can someone explain what 're the advantage
and the disadvantage of one vesus the other . Is the 1) slower and comsuming less current
than the # 2). For hi-speed design which scheme is prefered.
Thank you very much

Tomph

 

[amarnath]

Voltage divider question

as far as i know second scheme should be preferred,since it will be more faster.also the area occupied will also be significantly lesser in the second case than compared to the first case.

regards



amarnath

 

[tomph]

Voltage divider question

"as far as i know second scheme should be preferred,since it will be more faster.also the area occupied will also be significantly lesser in the second case than compared to the first case. "

So, in which case the scheme # 1) would be used ?
thanks
-tomph

 

[flatulent]

Re: Voltage divider question

Scheme 1 is used on filters to get a different terminal impedance compared to the internal impedance. The capacitors form part of the filter.

 

[tomph]

Voltage divider question

"Scheme 1 is used on filters to get a different terminal impedance compared to the internal impedance. The capacitors form part of the filter."
Could you please be specific in term of "terminal impedance" and "internal impedance"
thanks
-tomph

 

[flatulent]

Re: Voltage divider question

Go to **broken link removed** and scroll to the bottom schematic of the page. You can see a filter with capacitive dividers on the source and load end.

The 50 ohm loads on the input and output are called the terminating impedances. The impedance they present to the tuned circuits inside "internal impedance" is much larger and so the filter bandwidth is narrower.

The voltage divider effect also has an impedance transforming effect just like transformers.

The first part of the web page will give you all of the mathematics (possibly more than you want) in a step by step development.