TMP112: TMP112AIDRLR: V+ absolute max current

Hi Zoe,

The TMP112 has an Absolute Max Voltage of 4V. This is the most voltage that can be applied across the device regardless of current level. Current and voltage are intrinsically linked in ohm's law, so there isn't a need to also specify the max current the device could survive. 

The open drain outputs SDA and ALERT are rated for 3mA current sinking in their VOL specifications. If this current is exceeded, these output pins may fail to signal logic low and could sustain EOS damage. This current would pass through the SDA/ALERT pin to the GND pin, and would not be included in any power consumption (Iq) specification of the IC.

The ADD0 and SCL pins are high-impedance inputs that should not carry a meaningful amount of current into or out of the IC.

The power pin V+ is where we measure power consumption (Iq) of the IC. When the device is actively using its ADC to make a temperature measurement, it is consuming about 40uA. It only does this for Conversion Time, which is 30ms. This operation and current consumption is described in my app note https://www.ti.com/lit/snia026

There is one other scenario that causes current consumption at the power pin V+, and it is described in the TMP112 datasheet. Any time there is activity on the I2C bus, there will be additional current consumption in the TMP112's digital logic that scales with communication frequency. At the max bus frequency of 3.4MHz, the TMP112 may draw an additional 80uA due to the digital logic activity. This current would be in additional to the 40uA draw of the ADC if the two events were to occur at the same time. This would give us an expected max current of around 120uA.

thanks,

ren