48 pin package with 8 PWM outputs

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Anonymous
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Are there any easily available Psoc4 (or 5) chips in a 48 (or less) pin package that can do eight 13 bit pwm outputs + 1 uart rx

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Bob_Marlowe
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The amount of PWMs requires a PSoC5, no PSoC4 will do. PSoC5 start with 68 pin packages

   

 

   

Bob

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Anonymous
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Thanks, I guessed that was the case. I am trying to avoid using a qfn package and I don't want 60 unused pins on the qfp parts. 

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

slc, what PWM frequency range you are looking for?

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Anonymous
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I am using around about 7Khz.  The actual frequency is not critical but has to be high enough to avoid light strobing with cameras operating at a moderately high speed. 

   

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odissey1
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First comment on KBA 1000 replies posted 750 replies posted

slc,

   

Attached is example project of 8x PWMs controlled by UART commands. Project tested using PSoC4M (KIT-044), based on CY8C4247AZI-M485 (64pins) chip. It has 8 fixed function PWMs set to 13-bits each, operating at 5.86 kHz. PWM output frequency is defined by the PWM clock (48 MHz) and PWM period (8191 = 2^13-1).

   

To change PWM duty cycle, send UART commands, e.g.: 'A255', 'B8191', 'C0'.... etc. UART frequency set to 57600.

   

To increase PWM frequency try to change it to pseudo random PWM. This may have some non-linear effects depending on LED drivers used. 

   

Device selector provides a number of 48-pin and one 44-pin TQFP packages.

   

  

   

   

   

 

   

   

   

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

I have to admit to have been wrong! Great job, odissey!

   

 

   

Bob

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Bob, I was trying to sueeze 8 dithered PWMs into 4UDB on PSoC4, when noticed that it already has 8 fixed-function PWMs! With all PSoC possibilities we tend to forget about "standard" silicon features, which are plenty.  

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Anonymous
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Many thanks for the great effort. I should have stated, I am controlling these by dmx. This is all done and dusted with a psoc 5 and I am just trying to reduce the pcb footprint size.

   

This is where the 'easily available' part applies. I am working in the UK mainly as a prototype engineer and there is an utterly dismal selection of cypress chips available from the usual suppliers of parts in quantities < than 100 or so.

   

Maybe I can try Digikey or Mouser but I have been clobbered by import duty and taxes in the past when importing stuff so it is a last resort.

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

slc, I am still learning PSoC and uncovered few interesting things about P4 while working on this project. I have feeling that it can be further squeezed into P4200 with some trade-offs, but my guess this is not required. 

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Anonymous
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I am trying to consolidate and, as much as possible,  use one development system for all of the work that I do. I have been trying to do this for over 20 years and one day I may manage it.

   

Paying $15+ for a P5 does not go down well with production when I can do the job with a $1.50 chip from elsewhere.

   

I just did a quick search on the Farnell European website and they list 609 different chips from STM, 232 from NXP and 33 from Cypress. This is why choosing a Cypress chip is so difficult.

   

 

   

edit: I should have said immediately available, they actually list many more than this.

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