5V Sensor Power

Post Reply
safeng
Posts: 6
Joined: Wed Dec 09, 2015 10:04 pm

5V Sensor Power

Post by safeng » Sat Mar 11, 2017 1:49 pm

I have a custom sensor that I had working on a number of v12 WaspMotes that is no longer working on any for the v15 WaspMote I have tried.

The setup was that the sensor was powered from the WaspMote 5V Sensor Power Output and under software control was turned on and off. The sensor communications interface is a UART and it was wired to the Aux 1 TX and RX lines.

The sensors were working fine on a number of units with the V12 WaspMote.

I have now tried the same sensor with the V15 and it does not work properly.

The sensor powers on for a few seconds and then abruptly switches off.
If I measure the 5V Sensor Power Line it is turning off after a few seconds of powering the sensor and cannot be turned back on unless the WaspMote has its power turned off and back on. But when I run the WaspMote without the sensor connected the 5 Sensor Power stays on at 5V as expected. Also if I put the sensor on a V12 Waspmote it works fine.

My question is has there been a change with the V15 Waspmote with the 5V Sensor Power Output, the datasheets for both V12 and V15 indicate no changes and say the port can source 200mA.

Is there perhaps some current limiting or over current shutdown on the V15 for the 5V Sensor Power that wasn't on the V12.

A prompt reply would be most appreciated.

Thank you!

libelium-dev
Posts: 27967
Joined: Mon Sep 28, 2009 1:06 pm

Re: 5V Sensor Power

Post by libelium-dev » Mon Mar 13, 2017 10:22 am

Hi,

Are you using the battery? What battery level does Waspmote v15 have? Are you working with the last API v027?

Both Waspomote v15 and Waspmote v12 can supply a current of up to 200mA.

Regards.

safeng
Posts: 6
Joined: Wed Dec 09, 2015 10:04 pm

Re: 5V Sensor Power

Post by safeng » Mon Mar 13, 2017 10:44 am

Yes I am using the Battery and the Battery was showing 90% charged.

Interestingly the custom sensor has an optional module that uses a stepup 3.3V converter to create the 5V power required. When I use this the sensor with this module on the 3.3V SENSOR POWER line the sensor works fine.

But I would like still to use the sensor powered directly from the 5V Sensor Power Line as it will be more efficient on power consumption.

So my question is , if the two sensor power ports (3.3V and 5V) can both source the same current (<200mA) then why does the 5V sensor power line not work with my sensor but the 3.3V one does even though it is drawing more current because it also powering the 3.3v to 5V step up module.

libelium-dev
Posts: 27967
Joined: Mon Sep 28, 2009 1:06 pm

Re: 5V Sensor Power

Post by libelium-dev » Tue Mar 14, 2017 10:38 am

Hi,

We have just done some test in the 5V power supply and we have seen that the behavior is the same in both Waspmote v12 and Waspmote v15. We have verified that the power supply of 5V is able to supply the 200mA.

We are sorry but we don't know what issue there may be with your sensor.

Regards

Post Reply

Who is online

Users browsing this forum: No registered users and 1 guest