Power consumption (Naon)

Info Box Applies to Naon

Introduction

Providing theoretical maximum power consumption value would be useless for the majority of system designers building their application upon Naon module because, in most cases, this would lead to an oversized power supply unit.

Several configurations have been tested in order to provide figures that are measured on real-world use cases instead. Please note that Naon platform is so flexible that is virtually impossible to test for all possible configurations and applications on the market. The use cases here presented should cover most of real-world scenarios. However actual customer application might require more power than values reported here. Generally speaking, application specific requirements have to be taken into consideration in order to size power supply unit and to implement thermal management properly.

For an exhaustive description about power management on Naon and to understand power consumption connected to the available operating points (OPP), please refer to NELK Power Management section.

Set #1

Testbed

Measurements have been performed on the following platform:

• Naon SOM: DAF7910C0R
• carrier board: NaonEVB-Lite
• System software: NELK 1.0.0
• power monitor: INA226 (reference U20 of NaonEVB-Lite schematics).
• ARM Cortex-A8 frequency: 600 MHz
• SDRAM size: 512 MByte
• SDRAM frequency: 400 MHz
• HDVICP2 frequency: 306 MHz

Use cases

In the following table there's the summary result of data reported by INA226 in different checkpoint.

Checkpoint	Input Voltage [mV]	Shunt Voltage [mV]	Current [mA]	Power Consumption [mW]
Linux Prompt (M3 Unloaded)	3266	8	779	2550
Linux Prompt (M3 Loaded)	3261	10	1040	3400
cpuBurnA8 (M3 Loaded)	3258	12	1235	3900
decode & display H264 1080p60 on HDMI	3258	12	1219	3975
decode & display H264 1080p60 + cpuBurnA8	3255	14	1352	4450

Additional notes and reference:

• M3 Unloaded means that the two Cortex-M3 firmware has not yet been started (see /etc/init.d/load-hd-firmware.sh)
• for decode/display test the sample /usr/bin/runDecodeDisplayHDMI has been used
• cpuburn heavily uses Cortex-A8 and Neon to maximize power consumption and heat spreading. See the debian package information (burnCortexA8.s) for more information
• please note that shunt voltage value is rounded

Set #2

Testbed

Measurements have been performed on the following platform:

• Naon SOM: DAF7910C0R
• carrier board: NaonEVB-Lite
• System software: Naon Embedded Linux Kit (NELK) 2.0.0 Alpha
• power monitor: INA226 (reference U20 of NaonEVB-Lite schematics).
• ARM Cortex-A8 frequency: 600 MHz
• SDRAM size: 512 MByte
• SDRAM frequency: 400 MHz
• HDVICP2 frequency: 306 MHz

Use cases

Naon in Reset Mode (reset switch push down) 90m@12Vin

Gigabit Link Up 150mA@12Vin