TMS570LC4357: PLL core supply current

Roberto del Cano

Part Number: TMS570LC4357

Hi,

I would like to confirm what is the maximum current going through the PLL supply voltage pin which is a single terminal (terminal no. : P11) in the TMS570LC4357

Thanks

Roberto

over 2 years ago

0 jagadish gundavarapu over 2 years ago

TI__Guru 69891 points

Hi Roberto,

We don't have value of current consumed by VCC PLL only.

(+) TMS570LC4357: Max Current Req - Arm-based microcontrollers forum - Arm-based microcontrollers - TI E2E support forums

(+) TMS570LS3137: ICCPLL Current Max - Arm-based microcontrollers forum - Arm-based microcontrollers - TI E2E support forums

Thanks & regards,
Jagadish.

0 Roberto del Cano over 2 years ago in reply to jagadish gundavarapu

Prodigy 50 points

Hi- thanks for the support. So how should I approach to size (in terms of current rating) any circuitry connected to that supply input? such us a Low pass filter.

As the combined spec is 990mA spread across VCCPLL + VCC (12 BGAs terminals in total), as an asssumption would it be acceptable to divide the current seen by the pin as 990mA / 12

Thanks

0 jagadish gundavarapu over 2 years ago in reply to Roberto del Cano

TI__Guru 69891 points

Hi Roberto,

Roberto del Cano said:
As the combined spec is 990mA spread across VCCPLL + VCC (12 BGAs terminals in total), as an asssumption would it be acceptable to divide the current seen by the pin as 990mA / 12

It is not ideal way to do it, the current on VCCPLL will depends on PLL related configurations inside the controller. So, i will discuss with my internal team and get back to you on this.

Thanks & regards,
Jagadish.

0 jagadish gundavarapu over 2 years ago in reply to jagadish gundavarapu

TI__Guru 69891 points

Hi Roberto,

Theoretically the PLL current is typically under 10mA, but because there are two PLLs, the pin could see 20mA.

When we did practical measurement for one of our Hercules boards we got, current at idle (CPU suspends at a breakpoint in main()) is around 2.3mA (PLL1=PLL2=180MHz), and the current when performing SRAM reading and writing is around 3.2mA. Same measurement will be applicable for LC4357 as well.

Thanks & regards,
Jagadish.