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Need help finding an ADC to interface with the BS2... — Parallax Forums

Need help finding an ADC to interface with the BS2...

SteelSteel Posts: 313
edited 2006-10-11 00:39 in BASIC Stamp
All of the ADC's that are suggestions for the BS2 have input reference voltages of 0V and +5V.

I have an analog signal that swings from -5V to +5V.· I want to be able to read that signal with my BS2, but I can't find anything.· The TLC0831/32 ratings only read from 0-5V.

Has anybody worked with any ADCs that can have a -5V negative input reference and a 10+V differential?

please help

Shaun

Comments

  • Martin HebelMartin Hebel Posts: 1,239
    edited 2006-10-11 00:08
    You can use an op-amp in a summing configuration to add +5 to your input, resulting in a 0 to 10V signal, then you can use a gain of 0.5 to bring it back to 0 to 5V or simply use a voltage divider.

    -Martin Hebel

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    Martin Hebel
    Personal Links with plenty of BASIC Stamp info
    StampPlot - Graphical Data Acquisition and Control
    AppBee - XBee ZigBee / IEEE 802.15.4 Adapters & Devices
  • knightofoldcodeknightofoldcode Posts: 233
    edited 2006-10-11 00:39
    Steel said...
    All of the ADC's that are suggestions for the BS2 have input reference voltages of 0V and +5V.


    I have an analog signal that swings from -5V to +5V. I want to be able to read that signal with my BS2, but I can't find anything. The TLC0831/32 ratings only read from 0-5V.



    Has anybody worked with any ADCs that can have a -5V negative input reference and a 10+V differential?



    please help



    Shaun

    Look into the Max1270. Voltage readings are from -10 to +10. Input power voltage is +5V.

    Knight.

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  • Tracy AllenTracy Allen Posts: 6,664
    edited 2006-10-11 00:39
    Take a look at the MAX1270. It can acquire +/-5 volts even when using a single 5 volt supply.
    www.maxim-ic.com/quick_view2.cfm/qv_pk/1911
    Search this forum for discussion on how to use it with the Stamp.

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    Tracy Allen
    www.emesystems.com
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