Root causes of high deep sleep current [LoPy1, WiPy2 and SiPy], all the new modules **do not have deepsleep issues**

[robert-hh]

@Fred In another post on this blog I came along the voltage divider, which provides the battery voltage to P16 on the expansion board. At value sof 56k and 115k, this divider alone consumes about 20µA. Since most of the people aiming for deep sleep want to run the deive from battery, this is large compared to you aim at getting into the range of < 10 µA.

[daniel]

@robert-hh that's true. The redesigned expansion board (v3) will also include circuitry to shutoff that divider circuitry during deep sleep mode.

[RobTuDelft]

Glad the problem has been identified and that the Pycom team is dedicated to solving the issue.

A 20 mA deepsleep current was just under the limit to power our sensor stations for around a week on battery, but still very high of course. We are now looking for a solar panel solution in the mean while.

[PiAir]

Quick question: for Kickstarter backers, with "order number" you mean "backer number" ?

[Fred]

@PiAir Absolutely! Well noted. Thanks Fred

[exquisitus]

how would that work for customers who bought from a distriutor, in my case elmwood in toronto, canada? please advise. thanx.

[Fred]

@exquisitus Hi,

We want to keep it simple so just register your details on the Link I quoted and we will send out the deep sleep shield. If you can simply include the invoice/order number relating to your purchase from Elmwood then we can take care of the rest. Thanks Fred

[jasonriedy]

For those of us who were hoping to just plug in a LiPo, what is needed to power via the 3V3 pin?

And the total deep sleep draw of the current expansion boards is a tad over 2.5 mA when powered via that pin?

(As a software person looking for a quick & easy gizmo for relaying sensor data, I really was hoping just to plug a big-ish LiPo into the expansion board.)

[ssmith]

@Fred
I'm in the process of designing an adapter board to use a LoPy module in a sensor application. Can you make the details of the shield board available to possibly be implemented in my adapter board?

[constantinos]

@Fred Very Nice! Can you provide us also a schematic of the solution in order to fix our custom boards?

Thanks in advance
Constantinos

[daniel]

@jasonriedy what you need to do is to plugin the LiPo and attach the deep sleep shield that we just announced. The LiPo battery on the expansion board powers the module via the VIN (3.6-5.5V) pin, not via the 3V3 pin. Deep sleep with the shield will work on a transparent way when you issue the machine.deep_sleep() instruction.

[daniel]

@ssmith @constantinos we will make the schematics available later today.

[Fred]

@constantinos Hi, I can confirm that we will be releasing the schematic later today. Thanks Fred

[daniel]

Hello,

The schematics for the deep sleep shield are now available here: https://docs.pycom.io/pycom_esp32/_downloads/Deep-Sleep-Shield_Schematic.pdf

Cheers,
Daniel

[robert-hh]

@daniel Thank you very much. Will you also publish the code for the PIC controller?

[daniel]

@robert-hh yes, it will be open source too.

[frankb]

What are the dimensions of the 'deep sleep shield'? Will it still fit in a standard housing together with the v1.0 expansion board?

[daniel]

@frankb it's going to be around 12mm tall. It's not going to fit inside the Pycase, but it most likely will fit inside the IP67 case. We will confirm this shortly.

[Kean]

@daniel any timeline for release of the PIC source? I should have all the parts to build one of these on protoboard so I can continue with a project evaluation, except the code. Even a beta code in a hex file I can program via a PICkit3/ICD3.

[daniel]

@Kean I don't have precise timelines yet, we are still busy with the PIC code and we are not ready to share it yet. I should be able to share some more info next week.