TMP411: Not trigger fault during device turn on

Mike Yu

Intellectual 1830 points

Part Number: TMP411

Hi Team,

I want to follow up the further question of the E2E post below.

(+) TMP411: not using remote sensor - Sensors forum - Sensors - TI E2E support forums

Since the customer is not using the remote temp function, they had short the D+/D- together.

Is there any way that the device will not trigger fault during turn on?

We did read some of the register during boot up as below for your reference.

TMP411 Status register value

Addr…………………………………..Value

01 Remote Temperature in C 00

02 Status register value 88

03 Status register value 00

07 Status register value 55

08 Status register value 00

10 Status register value 00

11 Status register value 00

12 Status register value 00

13 Status register value 00

14 Status register value 00

19 Status register value 55

34 Status register value 00

35 Status register value 00

36 Status register value 00

37 Status register value 00

Best regards,

Mike

over 2 years ago

0 Ren Schackmann over 2 years ago

TI__Mastermind 35825 points

Hi Mike,

Under your diode condition, this device will always assert ALERT on power-up when the first conversion completes (~115ms after power on.) The only way to clear the alert is to use SMBus Alert Query shown in Figure 16. However, ALERT will assert again when the next conversion completes. To prevent further ALERTs being asserted, you can disable measurements of the remote channel. Setting the bit D4 in register 0x1A to 0 will disable remote measurements. You will still have to perform SMBus Alert Query to clear the ALERT after setting bit D4.

thanks,

ren

0 Mike Yu over 2 years ago in reply to Ren Schackmann

TI__Intellectual 1830 points

Hi Ren,

Thanks for your reply.

We still need the Alert not to assert during power up, because we cannot send any command before that.

I was thinking if we can replace the jumper with some value resistor or a diode.

Will it help during power up?

Best regards,

Mike

0 Ren Schackmann over 2 years ago in reply to Mike Yu

TI__Mastermind 35825 points

Mike,

The only way to avoid the issue is to connect a compatible transistor such as MMBT3904. See SBOA433 for a complete list of transistors we have evaluated.

thanks,

ren

0 Mike Yu over 2 years ago in reply to Ren Schackmann

TI__Intellectual 1830 points

Hi Ren,

Got it, thanks for the feedback.

Best regards,

Mike