- Sat Jan 19, 2013 5:06 pm
#154372
I have a project with a HIH-4030 / SEN-09569 analog humidity sensor. It's a 5V sensor but in the comments for the product it looks like it should work at 3.3V.
That's only half the problem though. I'm hooking this up to an XBee analog input which only has a range of 0-1.2V. I thought I could just use a voltage divider on the output to get me in the correct range. I'm not looking for super accuracy, just something that's consistent with my other sensors, even if it's consistently high or consistently low - I can accomodate that. Trouble is I'm just not getting any significant variation. When I first hooked it up it read a couple of points lower than my existing sensor so I thought all was good, but a few days later when the humidity had risen this sensor hadn't noticeably changed.
The XBee it's connected to goes in to sleep mode, but the sensor itself is permanently connected to the supply. My assumption is that this would avoid needing any warm up time before reading the sensor. Am I wrong? Do I need to take readings for a period of time to allow the sensor to stabilize?
I need more than one of these so I've bought another sensor and I'm going to go through the steps of getting it working with 5V, then with 3.3V, and then with 3.3V and a 1.2V output. Any suggestions on how to do the math from 5V to 3.3V and if the voltage divider is the right way of doing this would be greatly appreciated!
Nate: After testing, this sensor worked really well at 3.3V. You just have to linearly convert the 5V graph to 3.3V.I should be able to do that. I used to be really good at math, but obviously somewhere along the way I lost my mind.
That's only half the problem though. I'm hooking this up to an XBee analog input which only has a range of 0-1.2V. I thought I could just use a voltage divider on the output to get me in the correct range. I'm not looking for super accuracy, just something that's consistent with my other sensors, even if it's consistently high or consistently low - I can accomodate that. Trouble is I'm just not getting any significant variation. When I first hooked it up it read a couple of points lower than my existing sensor so I thought all was good, but a few days later when the humidity had risen this sensor hadn't noticeably changed.
The XBee it's connected to goes in to sleep mode, but the sensor itself is permanently connected to the supply. My assumption is that this would avoid needing any warm up time before reading the sensor. Am I wrong? Do I need to take readings for a period of time to allow the sensor to stabilize?
I need more than one of these so I've bought another sensor and I'm going to go through the steps of getting it working with 5V, then with 3.3V, and then with 3.3V and a 1.2V output. Any suggestions on how to do the math from 5V to 3.3V and if the voltage divider is the right way of doing this would be greatly appreciated!