the signal conditioning circuit

[tech_pro]

Hi

i need to design a circuit that could do the following

1- produce the square wave if the input is other than square wave
2- retain the wave shape if the input is square wave
3- the switching speed is 70ns

i was using the diffrentiator circuit but when input is square wave then i get no output

regards
uzmeed

 

[umesh49]

I could not think how exactly we can do it, but the right direction would be to think about some PLL based implementation.

 

[FreeMAn0110]

Are you looking to get square wave of one particular frequency or you want to vary the frequency and amplitude as well?

 

[FvM]

Try a clear specification.

 

[tech_pro]

Are you looking to get square wave of one particular frequency or you want to vary the frequency and amplitude as well?

this not a particular frequency could be any in the range of 2kHz to 300 KHz

uzmeed

 

[FreeMAn0110]

I think you can use Schmitt trigger based implementation. It will help you produce a neat square wave.
Schmitt Trigger Applications
Schmitt trigger - Wikipedia, the free encyclopedia

 

[tech_pro]

Hi

i am using the comparator lm 106 voltage comparator with diode

the circuit is responding well with the square input but when the input is changed like sine wave or the arbitrary wave the out is not that much accurate

could the type of diode is the reason or there is some thing else

regards
uzmeed

 

[FreeMAn0110]

Can you please post the output waveform. It might be useful to analyze.

 

[muthukumar_ece2004]

Use LM311 Comparator, it is convert sine wave to square wave and retain square wave if input is also square wave.

You can get the schematic from comparator application notes, otherwise replay me i will provide you!

 

[tech_pro]

Hi

here is my circuit



if i input a sine wave of 50KHz +/- 5V
the ouput is


and if i increase the frequency to 100k

the output is like this



same is the case with the square 50kHz



for sq 100k



now for triangularr 50k and 100k i hav



for arb wave of 50k and 100kHz freq




MY task is to measure the pulse width of the wave form in FPGA after being converting it in square with very small duty cycle say 10-20%

but these type of wave forms restrict the operational frequency

plz suggest any that can produce a perfect square wave irrespective of input waveform


@muthukumar_ece2004 plz provide the application note of LM 311

regards
uzmeed

 

[FvM]

The waveforms suggests, that you connected the LM106 incorrectly. Please post a complete schematic, showing how all pins are connected and which supply voltages are involved.

The criteria for selecting the comparator threshold and hysteresis are unclear. You also didn't yet mentioned the intended input voltage range.

 

[tech_pro]

hi

I m testing the circuit at 5V PP but the intended voltage is 0-24 V

i think it can that can be reduced to any range using potential divider

the power supplies used are +15/-15V

as described in data sheet

regards
uzmeed