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Currently I am using DHT11 in my project, but its not very sensitive, it is quite slow in detecting temperature changes.

What sensor could I use that will be more sensitive?

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You can use the LM35, is a Precision Centigrade Temperature Sensors with TO-92 package or SO-8 SMD package.

Here is a tutorial of how to use.

Its very simple to use it.

enter image description here

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I've tried a fair few different types... if you want just temperature, then i'd highly recommend the MCP9808 (http://www.adafruit.com/products/1782) - it's pretty quick to get a reading and you can put it into shutdown / powerdown mode and it consumes uA (although from my testing you need around 250mS for it to wake up). Very accurate too.

Also, I've recently been playing around with the Si7021 which also gives Humidity, it's a little slower than the MCP9808 but it is comparable for accuracy but with the obvious benefit of Humidity too. (http://www.ebay.co.uk/itm/Industrial-High-Precision-Si7021-Humidity-Sensor-with-I2C-Interface-Arduino-Hot-/231568758450?hash=item35ea92d6b2:g:8GMAAOSwpDdVRc8F)

I hope that helps :)

Cheers

Andy

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Sensitivity and slow acting are completely different. The slow devices will measure the temperature they just take longer.

For speed I would suggest a low mass thermocouple. The semiconductor devices are great but inherently slow because of the thermal resistance of the plastic case. As soon as you put the thermocouple in a jacket it will also slow down.

There are some boards that you can use that implement a K thermocouple.

Good Luck,

Gil

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If one wants a "highly sensitive" sensor, then the DHT's are terrible.

Terrible meaning: just ok accuracy, slow reaction speed, and long-term stability.

I've tried a bunch now- because my application needed a really good (see criteria above) temp and H and the SHT series by Sensirion definitely was the best I found. There may be others as good- you tell me.

Grab an SHT* (sht31-d for example, which has a nice i2c interface)- they're awesome. I've found the response times for humidity, for example, to be a few hundred ms.

Adafruit now has them on breakout boards ready to go for about $13.

For instance, if you put it against your skin, the H readings will start jumping.

I'm using these with great success.

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  • DHT22 does not suck. – Avamander Oct 24 '15 at 17:20
  • suck for my purposes- fast response, fast repeatable reads, long-term stability without the user needing to calibrate periodically. I will give you that they're more expensive. – dethSwatch Oct 27 '15 at 20:12
  • The price tag is according to the specs. You really can't expect more speed and precision for that money. – Avamander Oct 27 '15 at 20:25
  • Very well, I withdraw my remarks based on my experience with both DHT sensors- they clearly are the best and I can't understand why the original poster is not satisfied with their sensitivity and response times. I sincerely hope that he withdraws his question too since it casts aspersions on these fine components and I would be very sad were it that others were persuaded to use different sensors. – dethSwatch Oct 28 '15 at 14:11

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