LM95233: LM95233

Qammar Abbas

Part Number: LM95233
Other Parts Discussed in Thread: ADC12D1000RF,

Hi.

I am using a LM95233 temperature sensor in its default configuration to monitor temperature of ADC12D1000RF IC. However, i am getting a reading of 1 degree Centigrade continuously which doesn't look like the actual temperature of the IC being monitored. What adjustment do i need to make? Also please let me know the correct configuration of the diode select register in this case. Should i configure it for 65 nm or 90 nm process or an MMBT3904 transistor?

over 5 years ago

0 Amit Ashara over 5 years ago

TI__Guru**** 244380 points

Hello Qammar

Can you please let us know if you are reading the local or the remote temp sensor value? Also what is the I2C transaction for the register read look like, i.e the value of the register that you are reading?

As for the remote diode, what is being used. Perhaps a schematic of the connections would be useful for us to see.

0 Qammar Abbas over 5 years ago in reply to Amit Ashara

Prodigy 200 points

I am reading data from the remote 1 temperature register (0x11 MSB and 0x21 LSB address) whereas the pin for remote channel 1(D1+) is connected to temperature sensor pin of ADC12D1000RF IC. The I2C transaction structure is the same as you mentioned in my previous post and it works for the remote channel temperature. The remote channel 1 is by default configured to read intel 65nm or 90nm process diode.

0 Amit Ashara over 5 years ago in reply to Qammar Abbas

TI__Guru**** 244380 points

Hello Qammar

What is D- connected to from the LM95233 and what is the value being read out from the registers 0x11 and 0x21?

0 Qammar Abbas over 5 years ago in reply to Amit Ashara

Prodigy 200 points

D- is connected to D1+ via capacitor. The value read from registers 0x11 and 0x21 is 00000001 and 00100000 respectively which corresponds to 1.125 degree celsius. This is not the expected reading as the ADC12D1000RF IC is heated.

0 Amit Ashara over 5 years ago in reply to Qammar Abbas

TI__Guru**** 244380 points

Hello Qammar

The D- must also be connected to the Tdiode- . Is that the case?

0 Qammar Abbas over 5 years ago in reply to Amit Ashara

Prodigy 200 points

Yes it is connected.

0 Qammar Abbas over 5 years ago in reply to Amit Ashara

Prodigy 200 points

The remote channel 1 temperature is not according to my expectation. It stays in the range of 0-1.25 degree Centigrade. Please provide guidance regarding the issue. The hardware connections are correct and verified.

0 Amit Ashara over 5 years ago in reply to Qammar Abbas

TI__Guru**** 244380 points

Hello Qammar

Thanks for the information on the connections. Now having established that the connections are correct between the two devices, the next step would be to review the configuration of the LM95233. Can you please provide with the register values for the LM95233 device so that we can review the programming model.

0 Qammar Abbas over 5 years ago in reply to Amit Ashara

Prodigy 200 points

Hello Amit,

As i mentioned earlier, i am operating the device in its default configuration which means that i haven't configured any of its registers. I am using the default register values as mentioned in the datasheet. However, i tried writing to the Diode Model Select Register (0x30 Address) to configure channel 1 for MMBT3904. That didn't produce the required results.

0 Qammar Abbas over 5 years ago

Prodigy 200 points

Part Number: LM95233

Hi,

I am using remote channel 1 (MMBT3904) of LM95233 temperature sensor to monitor temperature of ADC12D1000RF IC. The temperature readings vary from 0-15 degree centigrade which is contrary to the expected readings. Moreover, the hardware connections have been reverified. Please let me know what adjustments do i need to make to get the correct temperature readings? Do i need to configure my offset register as well? Any guidance regarding the issue will be appreciated.

0 Amit Ashara over 5 years ago

TI__Guru**** 244380 points

Hello Qammar

Since it is a continuation of the same thread as earlier, we would use the older thread. Due to holidays, support is limited for this week, but surely we would work towards a resolution by next week.

0 Amit Ashara over 5 years ago in reply to Qammar Abbas

TI__Guru**** 244380 points

Hello Qammar

You would need to configure the device for TruTherm model. Also please make sure that the Remote sensor is enabled in the configuration registers for the LM95233

0 Amit Ashara over 5 years ago in reply to Amit Ashara

TI__Guru**** 244380 points

Hello Qammar

Is there any further update on the thread?

0 Qammar Abbas over 5 years ago in reply to Amit Ashara

Prodigy 200 points

Hello Amit,

The issue has been resolved. The unexpected temperature readings were due to a faulty IC. Thank you for the help.

Sensors

Sensors forum

LM95233: LM95233