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Incorrect temperature and pressure datae from MPL3115A2

Question asked by r krishnan on Sep 28, 2014
Latest reply on Oct 10, 2014 by JOSEPH LEHMAN

I am getting incorrect data from the MPL3115A2. I am triggering a single conversion by setting the OST bit in standby mode. Then I poll the OST bit until it gets cleared. Then I read the temperature and pressure registers. I am reading 15 deg C and around 32578 pascals.  The RAW bit and the OS[2:0] bits are all set. The temperature should be around 27 degC while the pressure should be around 101325 pa.  I am able to read the dev id register and I am getting 0xc4 as expected. I have an LM75B temp sensor, a light sensor (TSL4535), a serial eeprom  and an CC2D33S (humidity sensor) on the same i2c bus. There is no address collision.  Everything else is reporting valid data. I then verified that the temperature value reported by the MPL3115A2 increases when I directed hot air at the sensor. 

I have attached a pic of the sensor node which has this MPL3115A2 on board. Could it be that the sensor got damaged during hand soldering ?

sb1.png

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