Power consumption measurement on Vybrid

[alfred_liu]

Hi, Dear Vybrid team

I am learning the material AN4807 for Power consumption measurement.

I have a few questions for the measurement result:

1.       1. What’s the measure point for the following data? Is it 3.3V input? Or core 1.2V?

2.       2. What’s the CPU frequency for the following case?

3.    3. What’s the “reset status” meaning? Similar to “standby” status?

Many thanks

[jiri-b36968 · Accepted solution]

Hi Liu,

1. Mentioned data are from Datasheet ver.4 and show current consumption of the core voltage 1.2V. Please note that those currents strongly depends on the application - in real they are much less - all explained in mentioned AN4807.

2. Dual Core CA5 399MHz / CM4 133MHz. Please see chapter 3, where are described selected use cases.

3. Reset state is measured when reset is active - for example when reset button is pressed.

/Jiri

[Rodrigue]

Some additionall questions:

I need to extend the figures of the AN.

Lokking at the different tables, I see that 25C to 85C correspond to an increase of around 20% of the power consumption.

Then increasing the frequency of both core to 500/166MHz also increases of 20% the power consumption.

Since both have a mutual effect, and taking the Linux power consumption, I made the following extension.

For the cores at 25C 399/133 266mA should become 1.2x1.2x266=383mA at 85C 500/166.

My customer requested more accurate figures.

May we also specifiy more or less what each and every IP would consum under various operating conditions (Temp, Freq). Simulation values would be enough.

May we provide those data?

[jiri-b36968]

Hi Rodrigue,

in AN chapter 7.3 is table on temperature measurements. Also document on community vybrid_current_measurement_jiri.xlsx list 9.

it shows that different between 25 and 85°C is 36%.

Between 400 and 500MHz is 20%.

Hopefully it will help you. There is also document  with simulations - but it is not public.

/Jiri

[Rodrigue]

Hi Jiri,

thanks, I would like to get some of these docs with simulated values for the various IPs.

Not reveal all of them but to give indications for the customers power dissipation design.

[jiri-b36968]

Hi Rodrigue,

it is not public. Placed in Vybrid FAE space.DieSizeEstimation_Power_RunIDD_LKG_calculator_Sheet_V11_17May2012.xlsx

/Jiri