powering up the AD2 - blinking/flashing LED

[Telemeter]

I have questions regarding the electric power necessary to operate the AD2. In my project I am logging the voltage of a shunt of 10 mOhm. The resulting voltage is very low and the logger registers some noise. In order to reduce the noise I wanted to switch over to AUX Power and connected the only available 5 V / 1 A with my AD2. This did not result in any changes of the logged voltage. But I saw that the blinking LED within the AD2 was showing a new blinking pattern, now bilnking twice instead of once every second. Since my power supply does not match the recommended 2.5 A value I would like to know if the blinking signal is showing an alarm or just indicating the use of aux. power.

Klicking the status button in the waveforms window shows me Information on the voltage and current flow of the USB or AUX power supply. When the AUX power is applied, the voltage is slightly higer (5.2 V) and the current is lower than before, when USB power provided about 4.9 V only. Does the AD2 make use an internal swithing power supply or does it use power of both inputs.

Since I did not find anything about that blinking LED in the specifications I would like to raise the question about all functions of the blinking LED.

[JColvin]

Hi @Telemeter,

I have moved your question to a more appropriate section of the forum where the engineer most familiar with the AD2 functionality will be able to see and respond to your question.

Thanks,
JColvin

[attila]

Hi @Telemeter

The double Led blink indicates enabling of high current for the power supplies, when powering the device from AUX supply.
The AUX voltage should be 4.5-5.5V, the hardware power cutoff is below 4.11V or above 5.76V
By default the USB supply is cut when AUX is present, but it can be set to be always on under the device settings.

[Telemeter]

Thank you Attila,

I am late with this but I want to state that I have learned a lot by reading your answer. Thanks!!!