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01-03-2018, 10:58 AM
Hi guys,
I'm planning on powering my tinker-board through GPIO for maximum reliability, could I confirm that it's pins 2/4 == 5V, pin 6 == GND, up to 2.5A?
I will be powering a few USB devices and using the onboard Bluetooth and WiFi if that makes a difference.
Thanks in advance!
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01-04-2018, 04:32 AM
(This post was last modified: 01-04-2018, 04:34 AM by Arne.)
Hello,
yes I would confirm that pins 2&4 are directly connected to VCC_SYS bypassing the USB current-limiting power switch which is set to 1.2A.
VCC_SYS is then fed into the RK808 power management chip. The RK808 has 4 buck step-down regulators used for CPU(up to 5A), GPU(up to 5A), DDR(up to 3A) and IO(up to 2.5) voltages.
You will feed these directly as well as several linear regulators for MIPI(up to 150mA), Codec(up to 150mA), 1.8V-IO(up to 150mA), PLL analog power(up to 100mA), SD(up to 300mA), LCD(up to 150mA & 300mA) components.
So it depends how much current will be drawn but the RK808 has a recommended power dissipation of 2.5W. This is something to consider as the USB protection will not keep you from drawing to much current anymore.
Further is the USB Host Power directly connected to the 5V rail which you find on the header (plus a protection probably).
So hopefully these information answer or at least help you with your question.
Best regards
P.S. GND is connected to 6, 9, 14, 20, 25, 30, 34, 39.
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