TMP112: TMP112 address pin

NAOKI AOYAMA

Guru 11215 points

Part Number: TMP112

Hello,

> The device will detect the state of the ADDR0 pin each time an I2C transaction is initiated, so the pin

>should be allowed to setup and stabilize well before the transaction begins.

Is that really?

In another device with same function, it detected the pin connection at power on reset.

So, it is not possible to change the address unless the power off.

Is my understanding correct?

Regards,

Naoki Aoyama

over 7 years ago

0 Amit Ashara over 7 years ago

TI__Guru**** 244400 points

Hello Naoki-san

I am not sure where the statement is coming from, as I could not find the same in the TMP112 datasheet where ADD0 pin is either connected to V+ or GND. Also changing the ADD0 pin would mean a physical change on the board at run time which may not be an optimal solution.

0 NAOKI AOYAMA over 7 years ago in reply to Amit Ashara

Guru 11215 points

Hello Amit-san,

Thank you for your reply.

The statement is not on the datasheet. It is mentioned on the original question as below.

Of course, our customer don't change the address.

I want to know when does the TMP112 detect the condition of the pin connection.

Regards,

Naoki Aoyama

0 Amit Ashara over 7 years ago in reply to NAOKI AOYAMA

TI__Guru**** 244400 points

Hello Naoki-san,

I am looking into it, but as far as I understand, the address selection is done at run time when an I2C command is started to check what address is to be used based on connection of the ADD0 pin.

0 NAOKI AOYAMA over 7 years ago in reply to Amit Ashara

Guru 11215 points

Hello Amit-san,

Thank you for your reply.

If the customer change the connection of ADD0 pin with an analog switch or something
at between STOP condition and START condition, it seems to be possible to change the address.

Allow me to ask you one more question.
It is mentioned "Connect to V+ or GND" at description of ADD0 on the datasheet page 3 PIN FUNCTION table.
Is it possible to connect to SCL or SDA like Table 4 ?

Regards,
Naoki Aoyama

0 Amit Ashara over 7 years ago in reply to NAOKI AOYAMA

TI__Guru**** 244400 points

Hello Naoki-san

Yes, we will add the same in the next data sheet version

0 NAOKI AOYAMA over 7 years ago in reply to Amit Ashara

Guru 11215 points

Hello Amit-san,

Thank you for your reply.
I understood the selection of address.

Thanks,
Naoki Aoyama

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TMP112: TMP112 address pin