stevesmythe
Senior Member
I'm working on an improved version of my wireless AXE033 LCD weather station receiver/screen.With 3xAA zinc-carbon or 4xAA NiMH, when the LCD display goes dim, I know it's time to change the batteries.
I am drawn to the small size and low weight (and rechargeability) of a 2x3.2v LiFePO4 supply, regulated down to 5v. I'm thinking of using an LP2950.
My question is, what would happen in this scenario when the LiFePO4 voltage drops near to its recommended cut-off? The regulator minimum operating voltage is 5.5v (which would give me a bit of headroom before damaging the LiFePO4s), so will the output voltage collapse quickly below that - causing the display to dim? Is there any other way for me to tell, except by measuring directly with a voltmeter? I don't want to try it for fear of ruining a pair of expensive LiFePO4s.
I am drawn to the small size and low weight (and rechargeability) of a 2x3.2v LiFePO4 supply, regulated down to 5v. I'm thinking of using an LP2950.
My question is, what would happen in this scenario when the LiFePO4 voltage drops near to its recommended cut-off? The regulator minimum operating voltage is 5.5v (which would give me a bit of headroom before damaging the LiFePO4s), so will the output voltage collapse quickly below that - causing the display to dim? Is there any other way for me to tell, except by measuring directly with a voltmeter? I don't want to try it for fear of ruining a pair of expensive LiFePO4s.