TS-TPC-8390-4900 Power Consumption

From Technologic Systems Manuals

The TS-4900's power consumption can vary a lot depending on the build and activity of the board. Most of the power savings happens automatically when the cpu and gpu are idle, but it is also possible to disable the Ethernet PHY for additional savings. The backlight on the TS-8390 can be changed for significant power savings. No savings were observed putting eMMC or the ICE40 in reset.

# Put ETH PHY in reset
echo "116" > /sys/class/gpio/export
echo "high" > /sys/class/gpio/gpio116/direction

# Lower backlight to 50%
echo 4 > /sys/class/backlight/backlight_lcd.27/brightness

# Disable backlight
echo 0 > /sys/class/backlight/backlight_lcd.27/brightness

Ethernet is not connected unless otherwise specified, and serial is disconnected during the measurement. The CPU test is 5x processes of "openssl speed", and the GPU test is Qt5CinematicExperience in the Yocto image.

This test is using the TS-4900 800MHz industrial solo with eMMC and RTC.

TS-4900-1024-4096F-S8S-RTC-I + TS-8390
Test Max (W) Average (W)
CPU 100% + GPU loaded (LCD 100%) 9.36 (0.780 A) 6.98 (0.582 A)
CPU 100% (LCD 100%) 8.54 (0.712 A) 7.00 (0.583 A)
CPU Idle (LCD 100%) 7.89 (0.657 A) 6.66 (0.555 A)
CPU Idle (LCD 50%) 6.12 (0.510 A) 4.48 (0.373 A)
CPU Idle (LCD 0%) 4.79 (0.399 A) 3.48 (0.290 A)
CPU Idle (LCD 0%), LCD 3.3V off 3.98 (0.332 A) 2.92 (0.243 A)
CPU Idle (LCD 0%), LCD 3.3V off, Ethernet PHY in reset 3.76 (0.313 A) 2.52 (0.210 A)
CPU Idle (LCD 100%) + CPU Ethernet 8.1 (0.675 A) 6.79 (0.566 A)
CPU Idle (LCD 100%) + USB Ethernet 8.78 (0.731 A) 6.95 (0.579 A)

This test is using the TS-4900 1000MHz Quad core with eMMC, RTC, and WIFI.

TS-4900-2048-4096F-Q10S-RTC-WIFI-E + TS-8390
Test Max (W) Average (W)
CPU 100% + GPU loaded (LCD 100%) 13.49 (1.124 A) 10.75 (0.896 A)
CPU 100% (LCD 100%) 12.30 (1.025 A) 9.88 (0.823 A)
CPU Idle (LCD 100%) 8.26 (0.688 A) 6.50 (0.542 A)
CPU Idle (LCD 50%) 6.05 (0.504 A) 4.48 (0.373 A)
CPU Idle (LCD 0%) 5.01 (0.424 A) 3.48 (0.290 A)
CPU Idle (LCD 0%), LCD 3.3V off 4.64 (0.387 A) 2.95 (0.246 A)
CPU Idle (LCD 0%), LCD 3.3V off, Ethernet PHY in reset 4.20 (0.350 A) 2.56 (0.213 A)
CPU Idle (LCD 100%) + Hosting WIFI AP (0 clients) 9.06 (0.755 A) 7.07 (0.589 A)
CPU Idle (LCD 100%) + CPU Ethernet 8.54 (0.712 A) 6.58 (0.548 A)
CPU Idle (LCD 100%) + USB Ethernet 8.47 (0.706 A) 7.07 (0.589 A)