SNIS217C december 2020 – may 2023 TMP139
PRODUCTION DATA
Refer to the PDF data sheet for device specific package drawings
The TMP139 has two supply pins: VDDSPD which is the core supply, and VDDIO which is the IO supply. To ensure that the device starts up correctly, the application must power up VDDSPD first followed by VDDIO. Additionally, the power-on reset (POR) circuit is implemented to prevent improper operation in case of an incorrect power-up sequence.
As shown in Figure 7-2, the VDDSPD supply is applied first and must rise monotonically between VPON(min) and VDDSPD(min) without ring back. The VDDIO supply must ramp up next and must reach the correct level before any operation can be performed.
When the VDDSPD and VDDIO supply have ramped up above the minimum threshold values, the TMP139 performs the following steps:
The device always powers up in the I2C mode of operation.