howto battery-power a pic-project

[uclaros]

Hi all!

Just learning assembly and making my first "from scratch" code.

I'm building a UTP cable tester on a 16f84a and want to make it battery powered. if i use a 9v battery with a 7805 will it be a lot of wasted battery power on the 7805?

Is it better to use 4 AA 1.5v batteries?(I dont like the idea of 4 batteries!)

The power consumption of the project is low (16 leds, lighting up only 2 at a time)

Maybe I could use the 16lf84 that works on 2 volts and operate it with 2 AAs. But then is it ok for the leds?

Any advice is apreciated!

Thanks,

uclaros

[pay_c]

If you'll use accus:

Normal stuff (LCD&Core&stuff) about 30 mA (no backlight), LEDs (2) about 10-20 if resistance a little higher. That makes about 50 mA (through both the 7805 and the boards - the 7805 will just cut off the upper 4 Volts).

9 Volt battery (NiMH): 150 mAh - about three hours playtime..... ..... a little to less, isn't it?

I would stick to the 4 battery idea. AAAs: about 700 mAh (14 hours!), AAs: about 2000 mAh (40 hours !!!).

For the LEDs: There are minimal current LEDs available! They only use up 3 mA (you just have to go up with the appropiate resistance). The 2V thing could be a problem for the LEDs (it's at the border of them lighting up - but they should come up anyhow).

Greets!