Alkaline batteries

[estratos]

Hi,

I have a circuit powered from a 6V alkaline battery and the working voltage of my circuit is 3.3V. I initially designed the circuit to be powered through a LDO regulator but someone told me that a stepup-stepdown regulator would let me sink current from the battery, when the battery voltage drops below 4 V (My LDO won't work below 3.8 V I think). It seems that alkaline batteries provide a good portion of their charge under the nominal voltage.

Do you think if using a step-up/down regulator is worth the investment given the nature of alkaline batteries? Could anyone confirm that alkaline batteries need to be operated at lower voltages in order to take profit of their whole charge?

Thanks!