High sleep current issue with Funky v2 sorted out

The Funky v2 high sleep current situation turned to be my multimer going crazy when using a noisy 3.3V power supply. When powering the Funky v2 from couple AA batteries, I got 0.13-0.14mA sleep current using the sketch below. Still much higher than a Funky v1, I will probably be able to find more tweaks to get that lower, but not bad for an atmega32u4  node anyway. I suppose it has to do with some current flowing back the MCP1703 when the Funky is powered by a battery, see the MCP1703 block diagram:

[EDIT]: A good discussion on this issue here

mcp1703

//--------------------------------------------------------------------------------------
// harizanov.com
// GNU GPL V3
//--------------------------------------------------------------------------------------

#include <avr/power.h>
#include <avr/sleep.h>

#include <JeeLib.h> // https://github.com/jcw/jeelib
#include "pins_arduino.h"

ISR(WDT_vect) { Sleepy::watchdogEvent(); } // interrupt handler for JeeLabs Sleepy power saving

#define myNodeID 27      // RF12 node ID in the range 1-30
#define network 210      // RF12 Network group
#define freq RF12_868MHZ // Frequency of RFM12B module

#define LEDpin 1

//########################################################################################################################
//Data Structure to be sent
//########################################################################################################################

 typedef struct {
  	  int temp;	// Temp variable
  	  int supplyV;	// Supply voltage
 } Payload;

 Payload temptx;

void setup() {

  pinMode(LEDpin,OUTPUT);
  digitalWrite(LEDpin,HIGH); 

  rf12_initialize(myNodeID,freq,network); // Initialize RFM12 with settings defined above 
  // Adjust low battery voltage to 2.2V
  rf12_control(0xC040);
  rf12_sleep(0);                          // Put the RFM12 to sleep

  digitalWrite(LEDpin,LOW); 

  power_adc_disable();
  power_usart0_disable();
  power_spi_disable();
  power_twi_disable();
   //Leave timer 0 going for delay() function
  power_timer1_disable();
  power_timer2_disable();
  power_timer3_disable();
  power_usart1_disable();

  // Datasheet says that to power off the USB interface we have to do 'some' of: 
   //       Detach USB interface 
   //      Disable USB interface 
   //      Disable PLL 
   //      Disable USB pad regulator 

   // Disable the USB interface 
   USBCON &= ~(1 << USBE); 

   // Disable the VBUS transition enable bit 
   USBCON &= ~(1 << VBUSTE); 

   // Disable the VUSB pad 
   USBCON &= ~(1 << OTGPADE); 

   // Freeze the USB clock 
   USBCON &= ~(1 << FRZCLK); 

   // Disable USB pad regulator 
   UHWCON &= ~(1 << UVREGE); 

   // Clear the IVBUS Transition Interrupt flag 
   USBINT &= ~(1 << VBUSTI); 

   // Physically detact USB (by disconnecting internal pull-ups on D+ and D-) 
   UDCON |= (1 << DETACH);    digitalWrite(LEDpin,LOW);    Sleepy::loseSomeTime(100); //JeeLabs power save function: enter low power mode for 60 seconds (valid range 16-65000 ms)           } void loop() {      digitalWrite(LEDpin,HIGH);     power_adc_enable();   temptx.supplyV = readVcc(); // Get supply voltage   power_adc_disable();   digitalWrite(LEDpin,LOW);        if (temptx.supplyV > 2700) {// Only send if enough "juice" is available
    temptx.temp++;
    rfwrite(); // Send data via RF 
  }

  for(int j = 0; j < 1; j++) {    // Sleep for 5 minutes
    Sleepy::loseSomeTime(10000); //JeeLabs power save function: enter low power mode for 60 seconds (valid range 16-65000 ms)
  }
}

//--------------------------------------------------------------------------------------------------
// Send payload data via RF
//--------------------------------------------------------------------------------------------------
static void rfwrite(){
      power_spi_enable();
      rf12_sleep(-1);              // Wake up RF module
      while (!rf12_canSend())
        rf12_recvDone();
      rf12_sendStart(0, &temptx, sizeof temptx); 
      rf12_sendWait(2);           // Wait for RF to finish sending while in standby mode
      rf12_sleep(0);              // Put RF module to sleep 
      power_spi_disable();      
}

//--------------------------------------------------------------------------------------------------
// Read current supply voltage
//--------------------------------------------------------------------------------------------------
 long readVcc() {
   long result;
   // Read 1.1V reference against Vcc
    ADMUX = _BV(REFS0) | _BV(MUX4) | _BV(MUX3) | _BV(MUX2) | _BV(MUX1);  // For ATmega32u4
   delay(2); // Wait for Vref to settle
   ADCSRA |= _BV(ADSC); // Convert
   while (bit_is_set(ADCSRA,ADSC));
   result = ADCL;
   result |= ADCH<<8;
   result = 1126400L / result; // Back-calculate Vcc in mV
   ADCSRA &= ~ bit(ADEN); 
   return result;
} 
//###############################################################################################################

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  1. Pingback: Funky v2′s LDO to blame for high sleep current. Now fixed | Martin's corner on the web

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