TMS320F28386D: Functional Safety Manual: PLL

W Z

Part Number: TMS320F28386D
Other Parts Discussed in Thread: C2000WARE

In the Functional Safety Manual for TMS320F2838x Real-Time Microcontrollers(SFFS022 – DECEMBER 2022）

Only list the AUXPLL, there is no Device Partition for PLL module.

One question: Shall PLL module do the same Safety Feature or Diagnostic?

Another question: APLL2(PLL lock Indication) I cannot fing the suggestion from TI, shall it implemented as Power-On Self-Test or Periodic Self-Test?

over 2 years ago

0 Whitney Dewey over 2 years ago

TI__Guru 54415 points

I think the device partition field is mislabeled. "APLL" is referring to the PLL that both the SYSPLL and AUXPLL use. You'll always want to check the PLL lock status as you're configuring it at start up, but the working of the description says "use this signal as a critical interrupt/NMI" which seems to suggest a periodic check. I'll check with some colleagues for some more details and get back to you.

Whitney

0 W Z over 2 years ago in reply to Whitney Dewey

Expert 2390 points

Hello, I am following this question status, would like to know is there update?

0 W Z over 2 years ago in reply to Whitney Dewey

Expert 2390 points

Hello Any update information？

0 Whitney Dewey over 2 years ago in reply to W Z

TI__Guru 54415 points

Thanks for your patience. I have sent a reminder to my colleagues that we're still waiting for clarifications.

Whitney

+1 Whitney Dewey over 2 years ago in reply to Whitney Dewey

TI__Guru 54415 points

Discussed this with some colleagues and concluded that the description of this diagnostic needs some updates--for example, we don't actually support configuration of the lock indication tolerance on this device. You should still check the lock bit when you're configuring SYSCLK as shown the the C2000Ware reference code, but ultimately, the primary diagnostic you should be using to monitor the PLL is the DCC module.

Whitney

0 W Z over 2 years ago in reply to Whitney Dewey

Expert 2390 points

thanks.

Does TI provide the application notes to show which safety feature shall do Power-On Self-Test or Periodic Self-Test?

+1 Whitney Dewey over 2 years ago in reply to W Z

TI__Guru 54415 points

No, we don't provide any documentation like that because the answer of what's required to be run as POST vs PEST can be application or standard specific. I'd say in this particular case, I expect you'd want to be monitoring your SYSCLK continuously, either using CPU Timer 2 running off an independent osc source or using DCC.

C2000™︎ microcontrollers

C2000 microcontrollers forum

TMS320F28386D: Functional Safety Manual: PLL