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The TMP102 device is a digital temperature sensor ideal for NTC/PTC thermistor replacement where high accuracy is required. The device offers an accuracy
of ±0.5°C without requiring calibration or external component signal conditioning. Device temperature sensors are highly linear and do not require complex calculations or lookup tables to derive the temperature. The on-chip 12-bit ADC offers resolutions down to 0.0625°C. The module (HCMODU0100) provides header pins for power (3.3V), and to its digital I2C interface including bus pullup resistors.

PLEASE NOTE: This module does not include an on-board regulator. Do not power it above 3.6V otherwise you will cause permanent damage.




Features:

• Accuracy Without Calibration:
– 2.0°C (max) from –25°C to 85°C
– 3.0°C (max) from –40°C to 125°C
• Low Quiescent Current:
– 10-μA Active (max)
– 1-μA Shutdown (max)
• Supply Range: 1.4 to 3.6 V
• Resolution: 12 Bits
• Digital Output: I2C interface Compatibility







Raspberry Pi users:

For Raspberry Pi uses we have tested this module with the free Cayenne cloud based IoT software platform. Simply connect the module to your Raspberry Pi as shown below and use the Cayenne software platform to get remote temperature readings without writing a single line of code.




You can create a free account simply by clicking our referral link below:

• • • • • • • • • 

Arduino users:

To use this module with your Arduino please see the following connection diagram and sketch:











Disclaimer: The Cayenne platform is an external free service and is not provided by, or connected to, Hobby Components Ltd. It is therefore not being sold as part of the product advertised on this page. As such we do not provide any guarantees or warranties with regards to this service. Issues or questions related to the Cayenne platform should be directed to Cayenne and not Hobby Components Ltd.

Libraries, example code, and diagrams are provided as an additional free courtesy by Hobby Components and are not sold as part of this product. We do not provide any guarantees or warranties as to their accuracy or fitness for purpose.

Descriptions and diagrams on this page are copyright Hobby Components Ltd and may not be reproduced without permission.

Hi there -
Initially I coud only get a reading of 0.00 as the temperature using the sample sketch provided.

However I discovered that the call to the routine I2CReadInt() was commented out, so I changed the following piece of code (lines 65 - on) to readas follows (change is in bold, the comment terminator added).

float GetTemp()
{
int Data;
/* Set the sensors address pointer to the 16bit temp register */
I2CWritePointer(0);
/* Result is in the most significant 12 bits so shift it down. */
Data = I2CReadInt() >> 4;

/* Result is now in 12 bit two's compliment so convert it to 16bit
* two's compliment */
if(Data & 0x0800)
{
Data += 0xF000;
}

/* Result is now in 0.0625oC increments so adjust it for oC */
return Data * 0.0625;
}

Seems to work OK now

I hope this helps - Richard

Thanks for pointing this out. It looks like the closing */ on the previous line got accidently removed for some reason. I've now corrected the sketch in the first post.

A bit of further work on this one - trying to get a temperature logger to work, I found that polling at regular intervals gave the same temperature every time, even if I breathed on the sensor to heat it up. After a bit of head-scratching (and a trial of the Sparkfun example sketch) I found that the sensor performs better if you put it to sleep after every reading, and wake it up again for the next one.
Cheers - Richard

PS the drawing above semms to show a connection to the Arduino 5v output instead of the 3.3v one!

PS the drawing above semms to show a connection to the Arduino 5v output instead of the 3.3v one!

Thanks for pointing this out, I'll get it corrected ASAP