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TMS320F28069: TMS320F28069

Saad Pervaiz
Prodigy 120 points
Part Number: TMS320F28069
Other Parts Discussed in Thread: MSP430F5172

Hi,

Do any of the micro-controllers supporting floating point computations offer High resolution mode in their PWM timers, similar to the one in MSP430, where we can have higher clock frequency for the timer module.

Thanks,

Saad

  • 0
    TI__Guru 57255 points

    Hi Saad,

    The C2000 group of TI MCUs has its own method of generating high-resolution PWM outputs. 

    • The ePWM peripheral has a 16-bit timer & often can be clocked at the device's core frequency.  This ePWM has many additional features which can be useful in power converter applications (deadband generation, advanced trip capabilities, etc).
    • High-resolution (HRPWM) capability is some supplemental functionality that is built on top of many ePWM modules.  The HRPWM utilizes Micro-Edge Positioning & enables up to 150ps resolution.  This greater resolution often helps reduce the impact of the limit-cycle phenomenon.
    • The eCAP peripheral is a different peripheral which has a 32-bit timer and can be clocked at the device's core frequency.  This peripheral can be used for generating PWMs, but is more often used to measure duty cycles or frequencies of external signals.

    Many of our devices have floating-point capability and HRPWM features.  One such device is the TMS320F28069 (F2806x) that you mentioned.  Two other potential device families are the 'F28335 (F2833x) and the 'F28379D (F28x7x).

    http://www.ti.com/lsds/ti/microcontrollers-16-bit-32-bit/c2000-performance/real-time-control/overview.page
    http://www.ti.com/lsds/ti/microcontrollers-16-bit-32-bit/c2000-performance/real-time-control/getting-started.page
    Hopefully this helps!


    Thank you,
    Brett

  • 0 in reply to Brett Larimore
    Prodigy 120 points
    Hi Brett,

    Thanks a lot for your reply.
    I am actually using F2806x. As you mentioned, the timer in this can be clocked up to device's core frequency.
    I have previously used MSP430F5172, in which timer can be clocked up to approximately 8 times the core frequency. That provides finer resolution for variable frequency applications. However, MSP was limited in terms of its core frequency, floating point computations and A/D sampling rate.
    I was wondering if there is some other series which has the capabilities of the C2000 group, but where I can clock the counter at higher rates.
  • 0 in reply to Saad Pervaiz
    TI__Guru 57255 points

    Hi Saad,

    In the C2000 devices, we don't really have any true 'timers' that count faster than the core frequency.  The maximum is often the core frequency (SYSCLK).

    However, the HRPWM capabilities of the device may still meet the need you have.  Note that the high-resolution capability can apply to period, not just CMPA/B (duty cycle) values.  I'd recommend taking a look at this HRPWM's functionality to see if it will help you: 
    http://www.ti.com/lit/spruh18

    Note that the way the HRPWM works is complicated, which is why I hesitate to characterize it as just a timer.


    Thank you,
    Brett