Rak8212 and espruino: what is the lowest power consumption and how I could reach it?

[espruino-discuss]

Posted at 2019-07-12 by LorenzoG

Hello,
I'm using Espruino on the Rak8212 board and I would to know what is the lowest power consumption I can reach.
So i'm using the following program:

var iTracker;

function onInit()
{
  setTimeout(function () {
    Bluetooth.setConsole(true);
    
    iTracker = require("iTracker");
    
    iTracker.setCellOn(false, function () {
      print("cell off");
    });
    
    iTracker.setAccelOn(true, function () {
      iTracker.setAccelOn(false);
      print("acc off");
    });
    
    iTracker.setMagOn(true, function () {
      iTracker.setMagOn(false);
      print("mag off");
    });
    
    iTracker.setEnvOn(true, function () {
      iTracker.setEnvOn(false);
      print("env off");
    });
    
    iTracker.setOptoOn(true, function () {
      iTracker.setOptoOn(false);
      print("opto off!");
    });
    
    iTracker.setCharging(true);
    print("charg off");
    
    setTimeout(function () {
      setPmode("opendrain");
      NRF.sleep();
    }, 2000);

  }, 2000);
}

function setPmode(pm)
{
  D0.mode(pm);
  D1.mode(pm);
  D2.mode(pm);
  D3.mode(pm);
  D4.mode(pm);
  D5.mode(pm);
  D6.mode(pm);
  D7.mode(pm);
  D8.mode(pm);
  D9.mode(pm);
  D10.mode(pm);
  D11.mode(pm);
  D12.mode(pm);
  D13.mode(pm);

  D17.mode(pm);
  D18.mode(pm);
  D19.mode(pm);
  D20.mode(pm);

  D22.mode(pm);
  D23.mode(pm);
  D24.mode(pm);
  D25.mode(pm);
  D26.mode(pm);
  D27.mode(pm);
  D28.mode(pm);
  D29.mode(pm);
  D30.mode(pm);
  D31.mode(pm);
}

Furthermore, I detached the passive GSSN antenna because it produces a 10mA power consumption even with the BG96 module switched off.
Running that code I can get a 0.9mA power consumption.
Now, I would like to get a lower power consumption, in the order of 0.02mA.
Is it possible and how I could make it?
Thank you

[espruino-discuss]

Posted at 2019-07-15 by @gfwilliams

Hi Lorenzo - maybe you could ask RAK themselves?

Without anything running (eg. just after boot), Espruino should manage around 20uA from the nRF52832 chip (0.02mA), and with NRF.sleep(); Espruino should do 3uA.

So the increased power draw will likely be from the circuitry around the nRF52832, but I don't know enough about RAK's design to be able to help you out properly.

---

Posted at 2019-07-15 by LorenzoG

Hi Gordon,
thank you for your response.
I'll take your advice

---

Posted at 2019-12-02 by Kartman

RAK didn’t make a good choice of voltage regulator. This needs to be changed to one with a lower quiescent current.