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Battery choice — Parallax Forums

Battery choice

Mike15Mike15 Posts: 109
edited 2006-05-09 00:40 in BASIC Stamp
I am building a rocket payload that consists of an eeprom, RTC, two ADC's, and an accelrometer. Because of the weight I need to find a small light weight battery.
I don't know alot about the power supply end of things so bear with me. If I add up the supply currents I have 13 mA. I have the power connected to Vin to internally regulate the voltage to 5V.
I have already built a prototype using a 9V battery but this weighs almost 2oz.
Does anyone have a suggestion on a sutable light weight battery?

Comments

  • MCL9449MCL9449 Posts: 6
    edited 2006-05-06 12:56
    LiPo (lithium polymer). They are a bit expensive, but very light. They come in various capacities and in multiples of 3.7v.
  • allanlane5allanlane5 Posts: 3,815
    edited 2006-05-06 13:18
    I believe there's an "N" cell. And you can stack 'coin' cells.
  • Mike15Mike15 Posts: 109
    edited 2006-05-07 00:33
    Here is the schematic.

    The two ports are PC screw terminals so I can add with ease. In the future I will probably use a MAX186 instead of the 187.

    And if I understand SPI correctly I should be able to connect the SCK of each IC to 1 pin and the SI SO pins of each IC to 1 pin. I just need to connect each IC's CS to seperate pins. Right?


    Post Edited (Mike15) : 5/7/2006 12:05:03 PM GMT
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  • Bruce BatesBruce Bates Posts: 3,045
    edited 2006-05-07 04:20
    Mike -

    Selecting the proper IC via CS is generally fine, as is using common CLK and DATA lines.

    Regards,

    Bruce Bates

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  • Chris SavageChris Savage Parallax Engineering Posts: 14,406
    edited 2006-05-07 06:09
    Mike,

    ·· Perhaps I am missing something in your schematic, but you mentioned an RTC, but you don't seem to have one listed in that schematic.· You also have a crystal connected to the Digital Thermostat in the schematic.

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    Chris Savage
    Parallax Tech Support
    csavage@parallax.com
  • Mike15Mike15 Posts: 109
    edited 2006-05-07 11:55
    The DS1602 is a RTC from Dallas Semiconductor.
  • Chris SavageChris Savage Parallax Engineering Posts: 14,406
    edited 2006-05-07 18:29
    Sorry, I re-checked your schematic and last night my eyes transposed the 02 to 20...I thought you had the DS1620.

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    Chris Savage
    Parallax Tech Support
    csavage@parallax.com
  • Mike15Mike15 Posts: 109
    edited 2006-05-08 22:57
    I found a 12V 23A N cell that seems to work fine. Thanks for the help. In the next couple of days I'll post the whole project.
  • Bruce BatesBruce Bates Posts: 3,045
    edited 2006-05-09 00:40
    Mike -

    Just a friendly reminder. If/when you post your completed project, please do so in the "Projects" Section of this forum, as that's where folks will go to look for it. Thanks!

    Regards,

    Bruce Bates

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    Post Edited (Bruce Bates) : 5/9/2006 12:50:23 AM GMT
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