- Mark as New
- Bookmark
- Subscribe
- Mute
- Subscribe to RSS Feed
- Permalink
- Report Inappropriate Content
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
- Mark as New
- Bookmark
- Subscribe
- Mute
- Subscribe to RSS Feed
- Permalink
- Report Inappropriate Content
The amount of PWMs requires a PSoC5, no PSoC4 will do. PSoC5 start with 68 pin packages
Bob
- Mark as New
- Bookmark
- Subscribe
- Mute
- Subscribe to RSS Feed
- Permalink
- Report Inappropriate Content
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.
- Mark as New
- Bookmark
- Subscribe
- Mute
- Subscribe to RSS Feed
- Permalink
- Report Inappropriate Content
slc, what PWM frequency range you are looking for?
- Mark as New
- Bookmark
- Subscribe
- Mute
- Subscribe to RSS Feed
- Permalink
- Report Inappropriate Content
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.
- Mark as New
- Bookmark
- Subscribe
- Mute
- Subscribe to RSS Feed
- Permalink
- Report Inappropriate Content
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.
- Mark as New
- Bookmark
- Subscribe
- Mute
- Subscribe to RSS Feed
- Permalink
- Report Inappropriate Content
I have to admit to have been wrong! Great job, odissey!
Bob
- Mark as New
- Bookmark
- Subscribe
- Mute
- Subscribe to RSS Feed
- Permalink
- Report Inappropriate Content
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.
- Mark as New
- Bookmark
- Subscribe
- Mute
- Subscribe to RSS Feed
- Permalink
- Report Inappropriate Content
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.
- Mark as New
- Bookmark
- Subscribe
- Mute
- Subscribe to RSS Feed
- Permalink
- Report Inappropriate Content
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.
- Mark as New
- Bookmark
- Subscribe
- Mute
- Subscribe to RSS Feed
- Permalink
- Report Inappropriate Content
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.