LevelShifter Microcontroller ADC interface

[GOPALSWAMY]

Dear All

I want to monitor speed of metal object. I am using electro magnetic method to get speed signal
The output waveform is attached. The amplitude varies from +/- 1V to +/- 4V (Peak to Peak)
Frequency range is 100HZ to 600HZ. I want Low pass filter with level shifter with safe voltage level to interface ADC channel of Microcontroller. Require Single supply op amp 5V

Thanks in Advance

 

[KlausST]

Hi,

I don't know how to help, because there is no question in your post, nor do you tell where you see a problem.

Please post a draft of what you want to do (signal flow) .
Please give information why you want to use a low pass filter and why you need a level shifter.

It is not clear to me what signal you are interested in? Frequency only, waveform, amplitude...

Klaus

 

[GOPALSWAMY]

Hi,

I don't know how to help, because there is no question in your post, nor do you tell where you see a problem.

Please post a draft of what you want to do (signal flow) .
Please give information why you want to use a low pass filter and why you need a level shifter.

It is not clear to me what signal you are interested in? Frequency only, waveform, amplitude...

Klaus

Dear Klaus

Thanks for your interest on my Post

My requirement is to measure speed of a metal ring which is travelling @ 9,000 RPM to 18,000 RPM. I have constructed Iron Core Inductor with permanent magnet to get signal pickups in proportion to the rotating metal ring. The waveform structure is attached herewith.
The signal Amplitude is 1 V (peak to Peak) to 4V Peak to peak. To interface this signal to microcontroller I want to allow only +Ve portion of the waveform otherwise it may damage ADC of Microcontroller. Also I need more quantity of analog signal so I am using level shifter to get more linear output. Low pass filter is used to suppress noise signal with frequency more than 800HZ
Attached my schematic diagram. I just want to confirm this is good solution or any other efficient method is recommended

Best Regards
Gopal Swamy

 

[FvM]

I don't see a purpose of feeding the signal to the ADC. I would rather expect a pulse former and comparator that generates a single digital pulse per tachometer pulse.