What is a normal current draw for an arduino ATMega168 with nothing connected?
I'm building a handheld geiger counter using an ATMega168 microcontroller with the arduino bootloader. I was planning on using a 9v battery with a 7805 to power the circuit since the geiger counter power supply only draws 3ma and I did not think an arduino would draw much current. however, after building it on protoboard I found that the total current draw on the battery was in the neighborhood of 170ma and drained a fresh 9v in a few minutes flat. The rest of the circuit continues to work without the arduino, and draws only 20ma when the micro has been removed. is it normal for an ATMega168 or 328 to draw 150ma when loaded with a minimal program and none of its I/O pins are sinking/sourcing any current? It is possible this chip has been mistreated somewhat, would it being slightly damaged cause it to use more power than usual? maybe using sleep mode aggressively in my code to save power would work? also, does anyone know of a 5v regulator chip like the 7805 that does not use so much current? the 7805 burns up about 10ma by itself which is not so great when the geiger counter itself uses only a few ma.