Sallen Key Low Pass Filter, bandpass filter

[Maglatron]

Hello,

I would connect the Rlo to the REF.
You can likely use one buffer for at least 4 filters.

Bertus

so here:

Hello,

The Rhi is dependend on the signal you get out of the detector.
Set Rhi in such a way that the maximum of the detector shows all leds.

Bertus

ok cool think I have it now

 

[Maglatron]

Ref_out and Rhi the same value? just double checking should be!!
and the amps through each LED 12.5mA

 

[Maglatron]

so where in this schematic would I put the REF virtual ground, still pin 4??

 

[Maglatron]

I changed it for the REF virtual ground, but It's confusing me with the resistor setup

 

[Maglatron]

Little help please people?!?

 

[kellys_eye]

Little help please people?!?

errr, 325 replies to this thread not enough yet?

 

[Maglatron]

edited it some more!

 

[Maglatron]

Are long threads bad when I'm getting good results, I want to cascade the lm3914 im buying some LM3915's too I understand they're wired the same. my goal now is the last bit that I need, that is, how to hook up the envelope signal and virtual ground to cascaded bar graph LED's, in bar mode if you want to keep the thread short then just provide me with the answer and we will be done! new subject otherwise I'm going to have to keep muddling through and this site is a good resource, you guys are clever and I would bet my bottom dollar that you could give me the answer to my problem strait up! cheers

 

[Maglatron]

To be fair most of my questions could have been answered with "yes!" or "no!" or "This is how you..." I'm trying to get to the answer as fast as possible, believe me

 

[Maglatron]

you guys have taught me so much already from mic, to variable gain pre-amp, to filters, to virtual grounding of the filters for one power supply, to precision envelope detectors, now the last problem and it's grinding to a halt, I WILL get this done just need one more little nudge!! pleease
if you see this through to the end I will get results in the form of pictures and you will be able to see what you helped with!

 

[Maglatron]

my thread about the IR2110 chips and the inverter I made was quite long too!!

https://maker.pro/forums/threads/help-with-ir2110-chips.299598/post-1849995

but I got there in the end!

 

[bertus]

Hello,

Asking many times won't speed up replies.
This is an international forum with members all around the world.
Many members are likely in an other timezone as you.

Here is a circuit from a link that Delta Prime posted:


When you change that to the "lifted to REF" version, you will get this:


Bertus

 

[Maglatron]

THANKYOU so so so very much, LEGEND!!! I will bare in mind that it's an international forum, thanks again Bertus, I knew you would know, cheers
post 333 magic number!!!

 

[bertus]

Hello,

The voltage range from that circuit will be from 6 to 8.4 Volts, as the origenal is from 0 to 2.4 Volts.

Bertus

 

[Maglatron]

ok cool thank you which resistors do I change to go from 6 to 11.5? R2 and R3?

 

[Maglatron]

going to bed but again thank you for your help

 

[bertus]

Hello,

The voltage divider Rx/Rv1 can adjust the range.

Bertus

 

[Harald Kapp]

my thread about the IR2110 chips and the inverter I made was quite long too!!

It will help a lot when you put your collected questions and remarks into one single post instead of posting every thought separately, thus creating a string of subsequent posts.

 

[Maglatron]

so I understand that Rx / vR1 adjusts the range, and I want it to range from 6v to 11.5v what should I set the resistors at to achieve this, also you know the filter wizard does the order of the filter stages matter what order that they go in to get the desired result,? cheers

 

[bertus]

Hello,

Why do you want such high values?
Audio is not so high.
The 2.4 volts range is already quite high.
You might even need an amplifier between the filter and rectifier.

Bertus