Author Topic: Suggestions to reduce current consumption? (moteino + power shield+weatherboard)  (Read 1641 times)

xavier

  • Jr. Member
  • **
  • Posts: 65
  • Country: us
Hi there,

I'm trying to reduce the current consumption in my circuit (currently 1 mAmps during sleep) and I'm hoping someone on the forum has some suggestions to help me out...here are the details:

- I have sandwiched together a moteino, a power shield and my custom PCB that interfaces with a weather thingie (rain, wind speed and wind direction from Argent)
- I think I may have screwed up the power shield at some point (yep that should show you my level of understanding of EE :-) - I'll double check that later but long story short I'm powering the sandwich from the moteino now
- the 3 boards are connected only using headers side A0 -> GND

I've attached the schematic for the rain/wind board I made - I have not connected the mosfet, the BME280 works and in my code I set it in forced mode (goes back to sleep after measurement) - spec is here: http://www.mouser.com/ds/2/783/BST-BME280_DS001-11-844833.pdf and if I got it correctly current consumption is very low in sleep mode (0.3 uAmp max)

In my code, moteino boots and:
1- RainSensor Class  puts the BME280 in forcedMode, makes 1 measurement
2- Setup interrupts for rain and wind:
 pinMode(WSPEED, INPUT_PULLUP);  // Configure the pin as an input, and turn on the pullup resistor.
 pinMode(RAIN, INPUT_PULLUP);
 attachPinChangeInterrupt(WSPEED, wspeedIRQ, FALLING);

3- put radio in listening mode and low power down (and flash when present) - I'm using tom's code from https://github.com/TomWS1/RFM69_ATC/tree/ListenModeExtensions
    LowPower.powerDown(SLEEP_FOREVER, ADC_OFF, BOD_OFF);

I tried to not init the BME280 (spec says it goes to sleep automatically on power up) but current stays at 1mA - tried as well to use the Node_ATC_WL sample code but current stays at 1mA so I think my schematic is at fault - any suggestions on how to improve my setup? (I'm thinking cutting the pin on A7 in case of current leakage but that can't be 1mA...)

Anyhow, thanks in advance for any suggestions you may have,

X

Felix

  • Administrator
  • Hero Member
  • *****
  • Posts: 6377
  • Country: us
    • LowPowerLab
I have to ask, why did you need to include the PowerShield in this setup?

xavier

  • Jr. Member
  • **
  • Posts: 65
  • Country: us
I used the power shield to connect a solar panel to recharge the lipo, that was the idea anyway. Worked fine when I tried it on a breadboard...

X

Felix

  • Administrator
  • Hero Member
  • *****
  • Posts: 6377
  • Country: us
    • LowPowerLab
Ok so you use it simply as a charger. That should be fine. Something must happened between breadboard and final setup. You will need to somehow isolate the problem, identify which component is drawing the higher current. From your initial post it sounds like the BME280 sensor might be the issue.

xavier

  • Jr. Member
  • **
  • Posts: 65
  • Country: us
well it's definitely my board... I did cut A7 (connects to the power shield) and now I'm running at 560uA with somehow current keeping increasing to 650 after a couple of secs.

Anyhow, I'll try to make a new board with just the BME280 and see what happens... thanks!