Fixing low frequency of the PRS sequence

Tip / Sign in to post questions, reply, level up, and achieve exciting badges. Know more

cross mob
Anonymous
Not applicable

Hello Cypress Community

   

I am trying to use the PRS component in PSoC Creator. One of the requirements that I have is to fix the frequency of the PRS betweeen 100KHz to 200KHz. Essentially the Bandwidth should be 100 kHz, with fixed lower and higher frequency. How can I do this in PSoC ?

   

Virtually,

   

Sherlock

0 Likes
1 Solution
Bob_Marlowe
Level 10
Level 10
First like given 50 questions asked 10 questions asked

Due to the definition of "random" it will be difficult to fullfill your requirements. The maximum frequency you can get will be the clock-frequency divided by two (when the output changes at two adjacent pulses). but there is no theoretical limit for the lowest frequency. 

   

 

   

Bob 

View solution in original post

0 Likes
8 Replies
Bob_Marlowe
Level 10
Level 10
First like given 50 questions asked 10 questions asked

Due to the definition of "random" it will be difficult to fullfill your requirements. The maximum frequency you can get will be the clock-frequency divided by two (when the output changes at two adjacent pulses). but there is no theoretical limit for the lowest frequency. 

   

 

   

Bob 

0 Likes
Anonymous
Not applicable

I love google !! The lowest frequency is going to be clock /Resolution and the highest logic frequency (not switching harmonics) is clock/2.  \m/

0 Likes
Bob_Marlowe
Level 10
Level 10
First like given 50 questions asked 10 questions asked

Yes, as I said Clock divided by two, but your low frequency of 100kHz will not be easy to reach, even with a resolution of 2 bits and a clock of 400kHz.

   

 

   

Bob

Anonymous
Not applicable

or an input clock of 400kHz, maximum frequency from the PRS = 400kHz/2 = 200kHz.

   

And minimum frequency for resolution repeat cycle time 4 is 400kHz/4 = 100kHz. Correct ?

0 Likes
Bob_Marlowe
Level 10
Level 10
First like given 50 questions asked 10 questions asked

Yes, that is what I wanted to say. Since you may specify a resolution of 4, you'll get 15 different values (repeated) .

   

 

   

Bob

   

PS: I have been to Bakerstreet 221b

Anonymous
Not applicable

Ha, I see. How did I miss you.

0 Likes
Anonymous
Not applicable

Bob, could you provide me a much more discrete answer. What should I do to contain my frequencis between two known frequencies from a PRS component.

   

I can buy you a beer, if you could help me with this.

0 Likes
lock attach
Attachments are accessible only for community members.
Bob_Marlowe
Level 10
Level 10
First like given 50 questions asked 10 questions asked

Well, as I red your last posts and with what I know about PRS I would...

   

to make a long story short, see attached project and have some measures.

   

 

   

Bob

   

Any beer is taken/given only personally.

0 Likes