AD9833 Frequency sweep required

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IaCa_4674211
Level 3
Level 3
25 replies posted 10 replies posted 10 questions asked

Hello, Has anybody got the AD9833 component code and managed to create a frequency sweep?, the parameters I require are 1Hz to 60Khz at a rate of 30Hz, possibly adjustable by an encoder,

Kind regards

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1 Solution
odissey1
Level 9
Level 9
First comment on KBA 1000 replies posted 750 replies posted

IaCa,

The low frequency limit of 1Hz, and sweep rate of 30 Hz do not match. At sweep rate F_sweep=30 times/sec, the instantaneous frequency (in)accuracy for any output frequency is already 30 Hz. For example, the 1 kHz output is defined with accurcy 1kHz+/-30Hz. Therefore, to make any sense, the F_min should be larger than 30Hz (e.g. F_min=1kHz). Also other parameters are missing, like required number of frequency steps and accuracy.

What output waveform needed: square or sine?

What the encoder should control? Sweep frequency? In what range?

It may be possible to accomplish the goal by using PSoC internal frequency generator, like DDS24 or DDS32. Please take a look at these threads:

DDS24: 24-bit DDS arbitrary frequency generator component

Re: Generate variable frequency

/odissey1

View solution in original post

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1 Reply
odissey1
Level 9
Level 9
First comment on KBA 1000 replies posted 750 replies posted

IaCa,

The low frequency limit of 1Hz, and sweep rate of 30 Hz do not match. At sweep rate F_sweep=30 times/sec, the instantaneous frequency (in)accuracy for any output frequency is already 30 Hz. For example, the 1 kHz output is defined with accurcy 1kHz+/-30Hz. Therefore, to make any sense, the F_min should be larger than 30Hz (e.g. F_min=1kHz). Also other parameters are missing, like required number of frequency steps and accuracy.

What output waveform needed: square or sine?

What the encoder should control? Sweep frequency? In what range?

It may be possible to accomplish the goal by using PSoC internal frequency generator, like DDS24 or DDS32. Please take a look at these threads:

DDS24: 24-bit DDS arbitrary frequency generator component

Re: Generate variable frequency

/odissey1

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