Hi, I've got a question about the battery-life for a circuit with an oscillating load current.
The system I've designed uses no voltage regulation, and the current drain cycles from 14mA to 24mA at 600Hz, and works between 2.2V-3V. It alternates because the system enters low-power mode during each cycle of operation.
So far I've been using a 160mAh silver-oxide 3.1V battery (made up of four seperate 1.55V 80mAh cells). From measuring the voltage rail during operation I actually get a 2.65V signal with a 150mV, 600Hz sawtooth wave superimposed onto it, and this lasts for around 2.5 hours until the battery suddenly drops to 2V and the circuit stops working. When using 2xAA batteries the battery voltage during operation stays fixed at 3V (with no superimposed sawtooth wave).
I don't understand why the battery is draining so fast, but if you've got any suggestions then that'd be much appreciated. I need ideally as small batteries as I can get for around 5 hours operation. Thanks.
The system I've designed uses no voltage regulation, and the current drain cycles from 14mA to 24mA at 600Hz, and works between 2.2V-3V. It alternates because the system enters low-power mode during each cycle of operation.
So far I've been using a 160mAh silver-oxide 3.1V battery (made up of four seperate 1.55V 80mAh cells). From measuring the voltage rail during operation I actually get a 2.65V signal with a 150mV, 600Hz sawtooth wave superimposed onto it, and this lasts for around 2.5 hours until the battery suddenly drops to 2V and the circuit stops working. When using 2xAA batteries the battery voltage during operation stays fixed at 3V (with no superimposed sawtooth wave).
I don't understand why the battery is draining so fast, but if you've got any suggestions then that'd be much appreciated. I need ideally as small batteries as I can get for around 5 hours operation. Thanks.