I have a simple project built around ATMega8. It powers from a standard 9V battery with following 7805 regulator.
Unfortunately, it has quite a lot of quiescent current. In a sleep mode ATMega consumes around 0.8 mA when powered from 5V source directly, but powered from 7805 it is more like 3.8-4.0 mA. It approximates for about 2 months lifetime for 9V battery.
Is there any good way to minimize current?