Power supply issue by Vin on Sipy + Deep Sleep Shield

[robert-hh]

@nespressif There is no reason why you should not be able to supply a SiPy by connecting power to Vin and GND. I'm doing that in my own expansion board with Lopy, LoPy4 and Fipy, where the power from a separate USB/UART module is routed to Vin and GND, and I did that several times on the bench from a lab power supply in the absence of just another expansion board.

[nespressif]

@robert-hh Last night I tried to execute without the deep sleep shield and the behavior is the same, it shuts down in the first instruction.

I want to try with other programs (a simpler program that does not read sensors, just send a byte via Sigfox) and also with an external source that provides 5v stable.

Let's see if anyone has achieved to use Sigfox with a Sipy fed it directly through the Vin.

[robert-hh]

@nespressif I was wondering whether the power switch transistor of the deep sleep shield would cause a substantial voltage drop, but according to the schematics that is not likely the case. The transistor used has an ON resistance of 0.12 Ohm, which is pretty low.

[nespressif]

@robert-hh So far I have used the pysense and therefore I have not needed to use the ds shield, as you say. But now I want to use the Sipy without pysense and therefore I need the shield.

I have not tried to run only Sipy without ds shield, tomorrow I will try.

I think that the 3V3 Ultra-Low-Noise switching regulator that has integrated the Sipy can not feed it when it requires more consumption, but it is only an impression as I know very little about electronics.

[robert-hh]

@nespressif As @dan said, P8 may be an issue if you run the device with Exp. board 3 or PySense. In both cases, you do not need the deep sleep shield (as far as I remember).
I more seems like a problem of the power supply when using SIgfox the supply current increases. Did you try to run your code without the deep sleep shield?

[nespressif]

New tests: today I tested with a new Sipy and a new ds shield. Using the expansion board v2.0 I have updated the firmware of the Sipy, finished the update begins to work with the heartbeat LED. The Sipy + ds shield, (without expansion board) with the heartbeat works perfectly if I feed it with a 3.7v lipo battery or with an external power supply to 3.3v (ATX) directly through the Vin.

Then I have programmed the Sipy with the program that sends data using Sigfox, and with this program it doesn't work if I feed it with the 3.7v battery nor with the external power supply. It starts to run but turns off.

I want to try the P8, although I do not think it works, because that was for the Expansion 3, as I read. And I also want to try feeding it with an external 5v power supply. The ATX source output gave me 5.75v and I didn't want to risk, because it's out of range, I'll try a resistor when I can.

Any idea why it doesn't work?

[nespressif]

Hello, @dan, thanks for your response, and to @robert-hh thanks, too.

I think I haven't explained myself well, I don't have an expansion board v.3 I have the version 2 and several Sipy and several pysense. The expansion board v.2 I only use it to program the Sipy, then I want that they work only the Sipy connected to the deep sleep shield, without expansion board. With the sipy + ds shield + exp. board 2.0 powered by USB everything works perfectly.

After programming the module inserted in deep sleep shield, I have fed it with a lipo 3.7 battery, the positive cable connected to the Vin and the Gnd to the Gnd (directly without exp. board). So it works fine with programs like blinker and the heartbeat LED work fine, but it doesn't work with programs that use the Sigfox network.

I've also tried a 3.3v protoboard power supply and I got the same behavior, it works fine with "light" programs but not with Sigfox. I want to try feeding it with 5v in the Vin, to see if it works and also test what Robert-hh says, connect the P8 to the output pin 3v3. But I haven't had time yet.

Regarding the transfer of contracts between Sigfox devices, I have found this post, but as it does not clarify much, I would like that if you can consult Sigfox, because I do not have access to support queries, that sure you can do. Well, it's interesting to know, since damaging a Sipy can happen to anyone. At the moment I have suspended the Sipy in the backend.

I asked this question in the Sigfox Support forum

Regards and thanks.

[dan]

@nespressif Does the heartbeat LED work? As for the Sigfox contract, you can activate the other SiPy as well. Not sure if you can transfer contracts between devices.

[dan]

@robert-hh that was related to the Expansion Board 3, it shouldn't be an issue with v2

[robert-hh]

@nespressif I remember faintly there there was something related to P8. There was a thread in the forum, you may find it by searching. So try to pull P8 either low or high.