AnsweredAssumed Answered

AD5933, IC does not generate Vout signal using low frequency external clock.

Question asked by k.sharma on Jun 15, 2016
Latest reply on Jun 17, 2016 by k.sharma

I am using IC AD5933 to measure impedance. I communicate with the IC using Arduino Yun. I want to measure impedances from frequency range 1 Hz to 100kHz. I do not perform a frequency sweep but measure frequency at certain discreet points. The system works fine for frequencies greater than 1 KHz when I use the internal clock. I also tried using an external crystal oscillator to provide an external clock of 1MHz at Mclk and got good results upto a frequency of 350Hz. Next, I wanted to provide a lower clock to measure frequencies lower than 300 Hz with good accuracy. I tried 32.768 KHz external clock http://www.abracon.com/Oscillators/ASVK.pdf but did not get any result. Using an oscilloscope I found that AD5933 is not giving out a sine wave. I programmed start frequency as 100Hz or lower but did not get any result. I also tried providing an external clock using NE555P timer at clock frequency 52 kHz , 76kHz, but still no result.

 

Could anyone please guide me where could the problem be? I do not have much experience with circuits and arduino coding, and I have no idea what could be going wrong.

 

Any help is greatly appreciated.

Thnakyou.

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