Low Power/Standby mode XU316

[kubaG]

Hi everyone,

I'm working with the XU316 and aiming to achieve lower power consumption (some kind of standby mode), ideally at least between 100-200mW. I've been trying to configure the SystemFrequency and ReferenceFrequency values in the .XN file to help reduce power consumption. However, whenever I set the ReferenceFrequency or SystemFrequency to less than 100 MHz, I keep encountering the error:

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[build] XNHandler: Error: XN11108 Reference clock frequency (100000000) may not be greater than or equal to the PLL frequency (100000000).

for:

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<Node Id="0" InPackageId="0" Type="XS3-L16A-1024" Oscillator="24Mhz" SystemFrequency="100Mhz" ReferenceFrequency="45Mhz" >

I tried multiple frequency combinations and nothing worked.

The best power results I've been able to achieve so far are around 450mW on a 5V supply and approximately 230mW on a 3.3V supply.
Setting on both tiles:

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write_tile_config_reg(tile[1], XS1_PSWITCH_PLL_CLK_DIVIDER_NUM, 6);
setps(XS1_PS_XCORE_CTRL0, 0x10);

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write_tile_config_reg(tile[0], XS1_PSWITCH_PLL_CLK_DIVIDER_NUM, 6);
setps(XS1_PS_XCORE_CTRL0, 0x10);

Also i was not able to configure write_tile_config_reg/ XS1_PSWITCH_PLL_CLK_DIVIDER_NUM for value larger than 6.

Currently I am using 24 MHz crystal, switching to 1.8V oscillator might help ?


I just need some kind app that bootloader will load and keep chip in standby and will listen for button IRQ or something. In datasheet i found this :
• Standby: 5 mA (typical)
but how can i achieve that?
Any advice that could help me achieve power consumption within my target range would be greatly appreciated.

Thanks in advance!

[Ross]

Look out for application notes AN02023: xcore.ai Power Consumption Estimation and AN02022: xcore.ai Clock Frequency Control being made available in the next few (working) days.

[Ross]

AN02022: xcore.ai Clock Frequency Control

[Ross]

AN2022: xcore.ai Power Consumption Estimation