Connect with us

boosting battery voltage

Discussion in 'Electronic Basics' started by Joe, Apr 25, 2004.

Scroll to continue with content
  1. Joe

    Joe Guest

    I have an application where I need to use 5V (433MHZ receiver module). I am
    using batteries (alkaline 1.5V). I have tried using 4 batteries and then
    using a diode to drop the voltage to about 5.4Volts, but, because of space
    constraints in this project, I was wondering if there is any such (fairly
    simple) circuit that would allow me to use 3 batteries (total 4.5V) and
    somehow get my 5 volts. The spec of the RX module is 4.5 to 5.5 Volts, but
    it does not seem to perform very well at 4.5V so I would like to use at
    least 5Volts. Is this possible?

    If I know what it is called, I can google for it.

    TIA,
    Joe
     
  2. Joe,

    Google for "boost mode smps"

    petrus
     
  3. Gareth

    Gareth Guest

    Yes, there are ICs which do this.

    Look for Switched Mode Power Supplies (SMPS), switching regulators or
    DC-DC converters. There are devices which can step the voltage up and
    devices which can step the voltage down, obviously you want the "boost"
    or "step up" type.

    National Semiconductor have a good selection of ICs, see:

    http://www.national.com/parametric/0,1850,1758,00.html

    see also:

    www.maxim-ic.com
    www.linear.com
    www.ti.com


    --
     
  4. Gary Lecomte

    Gary Lecomte Guest

    You could possibly use a ICL7660, and only two batteries. It will almost double it.

    Gary
     
  5. Colubris

    Colubris Guest

    Hi Joe,
    Try "DC to DC converter" (or similar) "step up" "Switching power
    supply" "boost converter"
    Might have an easier time just trying different style / chemistry
    batts though.

    Good Luck,
    Arch
     
  6. Joe

    Joe Guest

    Thank you, Petrus. Lots of hits, I will have to sort thru them. I was
    hoping to find a simple circuit that I could build myself to do what I need.
    There are some circuits out there that show basically an inductor, a switch,
    and a cap or RC network. The switch looks like some kind of transistor, but
    It didn't show what was driving it. Anyway, at least now I know what to look
    for.

    Joe
     
  7. Joe

    Joe Guest


    Thanks for the links, Gareth. I will be sorting thru those sites the next
    few hours.

    Joe
     
  8. Hi Joe.

    Go to http://www.linear.com/software/, and download LTSpice (its free.) If
    you install it, and open "switch selector guide" from the file menu, it'll
    prompt you for input and output voltages and current requirements, and then
    design a SMPS for you automatically (using one of linear's parts, of
    course.)

    You can also build these from discrete components, but its going to be
    simpler to get something going with one of these chips and a few spare
    parts.

    Regards,
    Bob Monsen
     
  9. Jamie

    Jamie Guest

    if the receiver is not drawing to much you can get a DC-DC converter chip.
    they have some average ones that can produce up to 1 amp using power
    source as low as .9 volts the last time i looked.
     
  10. Joe

    Joe Guest

    Hi Gary,

    Thanks for that info. The ICL7660 only supplies 10mA, but, while on that
    same page (Maxim), I found the maxim 1759. I am not sure yet if this will
    work, but I will keep looking. My requirement is now to be able to use 2 C
    alkaline cells to generate 5V for a 433MHZ receiver module and its
    associated decoder (HT12D). When the data is received, at first, all I plan
    on doing is usint a nor gate latch and flashing a LED (~20mA), but
    eventually I want to turn on a solenoid to press the shutter button on a
    camera (will need possibly up to 200mA).

    I found a home brew boost converter on the web somewhere and have only
    LTspiced it so far, but it looks like it is very load sensitive and draws a
    huge amount of current when the transistor is on. I can post it to ABSE if
    anyone is interested.

    Joe
     
  11. Joe

    Joe Guest

    Thanks Arch,

    Is there a such thing as a 5Volt battery that's not terribly expensive?
    (This is a hobby project, probly one or two at most). If not, what would you
    suggest for style/chemistry? I need 5 volts and at least 50mA capability,
    possibly more if I use a solenoid.

    Joe
     
  12. Joe

    Joe Guest

    Thanks Robert,

    I have LTSPICE, but did not think to look at their components. I seem to
    remember that their ICs needed a lot of spare components. I can check again.
    Just scroll down the component list. Maybe I shoul ask on the yahoo LTSPICE
    list I am on, duh! (LOL)

    Joe
     
  13. Joe

    Joe Guest

    Thanks Jamie,

    1 amp would be more than adequate, Any part numbers come to mind?

    Joe
     
  14. But do they still sell their chips in thru-hole versions? Most of what
    I see on Maxim is surface mount.
     
  15. Joe

    Joe Guest


    Thanks for the info, watts. Just about everything i am finding is surface
    mount. I did find something in the mouser catalog and I ordered a couple of
    them today to see if they will work. The part number is ST619LBN. It comes
    in a dip 8 package and you just have to hang 4 capacitors onto it.

    Joe
     
  16. Rich Grise

    Rich Grise Guest

    It's probably just laziness on my part, but if I had room for two C
    cells and a SMPS, I'd probably use 4 AAs and a diode.

    Have fun!
    Rich
     
Ask a Question
Want to reply to this thread or ask your own question?
You'll need to choose a username for the site, which only take a couple of moments (here). After that, you can post your question and our members will help you out.
Electronics Point Logo
Continue to site
Quote of the day

-