Power question about SX28 and Parallax 2x16 LCD.
T&E Engineer
Posts: 1,396
I am trying to design a circuit that will use an SX28 and an LCD. I want to know if it is possible or acceptable to use 2 AA batteries. It is possible I can upgrade it to 4 AA or worst case a wall transformer regulated back to 5vdc. The later case is worst case for appearance of the project.
I am adding an LCD and SX28 to a digital counting bank. See a previous post in this forum for details to this. Or below....
http://forums.parallax.com/showthread.php?p=660476
I have dremelled out the space for the 2x16 Parallax LCD and got it to fit. The coin bank normally ran on 2xAA batteries with a very small custom lcd and unknown microcontroller. I am replacing everything with an SX28 and LCD. I can probably dremell out the 2xAA battery case and put in a flat 4xAA like the one in the BOEBOTs. However, since the LCD has a backlight I would like to leave it on but afraid to kill the batteries.
I could have a wall transformer plug into the side of the screw on top but don't know how bad this might look. It would certainly solve power problems.
PS: I would also like ideas on how to add input (switches or keypad, etc.) to add user pin codes or something·to keep track of individual money accounts in the bank.
There is so much potential to this cool project knowing that I can control what happens and is displayed on the screen.
Thoughts...Comments?
Thanks for your help!
I am adding an LCD and SX28 to a digital counting bank. See a previous post in this forum for details to this. Or below....
http://forums.parallax.com/showthread.php?p=660476
I have dremelled out the space for the 2x16 Parallax LCD and got it to fit. The coin bank normally ran on 2xAA batteries with a very small custom lcd and unknown microcontroller. I am replacing everything with an SX28 and LCD. I can probably dremell out the 2xAA battery case and put in a flat 4xAA like the one in the BOEBOTs. However, since the LCD has a backlight I would like to leave it on but afraid to kill the batteries.
I could have a wall transformer plug into the side of the screw on top but don't know how bad this might look. It would certainly solve power problems.
PS: I would also like ideas on how to add input (switches or keypad, etc.) to add user pin codes or something·to keep track of individual money accounts in the bank.
There is so much potential to this cool project knowing that I can control what happens and is displayed on the screen.
Thoughts...Comments?
Thanks for your help!
Comments
Just one comment ... or maybe 2 .. cool idea neat project.
Since you wish to use the back light I would recommend using a Wall plug.
You would drain a battery really quick ..
cheers
Ronald Nollet Australia
However, after thinking about it a bit more, I was thinking of only adding backlight when a coin is dropped in which may only stay on for a few seconds at any one time.
If I do stay with Battery useage, do I have to use 4xAA or even a 9v ? It looks like it will need 5v but not sure if the LCD could run on 3v (as I know the SX28 could). I know the 9v would provide much less current but would be easier to regulate to 5v with a 7805. I don't know if 6v can directly be used with the SX28 and LCD.
Can someone confirm this?
Thanks.