Voltage divider for xBee and sensor
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Voltage divider for xBee and sensor

by dsbach on Tue Nov 27, 2012 11:01 am

I want to use the Honeywell HIH-4030 (analog) humidity sensor with an xBee.
xBee requires 3.3Vdc and the sensor 5Vdc.
I will be supplying power via a wall wart (most likely 5Vdc).
What products do you have to allow each device to have its proper voltage?
You have two level splitters. Is one more suitable than the other?
Or would a custom layout be better?
Thanks,
db
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Re: Voltage divider for xBee and sensor

by adafruit_support_bill on Tue Nov 27, 2012 11:40 am

Our 3.3v DC/DC converter is a little overkill for powering an XBee, but it would be more efficient than a linear regulator. https://www.adafruit.com/products/1066
A simple resistor divider can be used to scale the 5v analog output from the sensor to the 3.3v range of the the XBee.
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Re: Voltage divider for xBee and sensor

by dsbach on Wed Nov 28, 2012 3:20 pm

Thank you! You provided some terms I needed to use for searching.

Also, I stumbled across these specific instructions in a link from SparkFun:
http://dlnmh9ip6v2uc.cloudfront.net/dat ... rface3.pdf

Except for the prototyping board where I would start off using a breadboard, it was quite helpful to me.

(I haven't built this yet, so I don't know exactly how well it works.)
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Re: Voltage divider for xBee and sensor

by dsbach on Sun Dec 02, 2012 12:33 pm

I came across more helpful information on mating a 5V sensor with an xBee in Tom Igoe's Making Things Talk, second edition, project 13 about sensing toxic chemicals. The part about creating a sensor module with xBee is directly related to my inquiries, although it uses a gas sensor.
Also quite interesting is the way to cause the receiving module to trigger a closed connection on the receiving Series 1 xBee using a PWM connection. I believe this doesn't work on a series 2 xBee.
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