Current draw of the pcb versions of the beverage sensor

Just finished assembling a second unit of the liquid level indicator. I should give dad half a dozen--he's too concerned about breaking and overusing the gadget. Found a balloon whisk made of stainless steel wires. Used that for the probes. Now corrosion won't ever be a problem (hopefully).

All along I've been measuring the currents of a breadboarded circuit. It was only prudent to check to see how the pcb versions are doing. Both units have been loaded with the latest firmware version. Here are the values I got for the two units. 

Standby mode	Current (µA)			Battery voltage (V)
	Max	Min	Ave
1st unit (April 28)	2.05	0.48	0.74	3.099
2nd unit (May 6)	2.29	0.56	0.80	3.207

The earlier unit didn't use a new battery. Its initial voltage was around 3.14 when I installed it in the circuit. The latest unit does use a new one. With a higher voltage than the 3.0V of the breadboarded version the higher currents are surprising. The latest unit, however, seems to be drawing a lot more current. But it seems to be within the specs of the MCU. Then again there could be some leakage current along the board.

I failed to mention in the last post that I also measured the DAC and voltage comparator currents in the breadboarded version. I modified the firmware so that the comparator was kept enabled throughout. I then measured the standby current. Thereafter, I changed the firmware back to its original form and kept the DAC enabled throughout and measured the standby current. I obtained a DAC current of approximately 19µA and a voltage comparator current of around 4.5µA. Enabling these modules only during probe reads does indeed help minimize power consumption.