6 Conversion Time and Resolution Setting Highlights

Texas Instruments is making new technology that improves conversion outcomes. Conversion time describes the time it takes to make a new temperature measurement. The device resolution and conversion time are inversely related. In general, the higher the resolution, the more time required for the device to output a new temperature measurement. This relationship is described with TMP275, TMP175, and TMP75 in Table 6-1. TMP275, TMP175, and TMP75 have programmable ADCs, where users can choose from a 9-bit resolution mode to a 12-bit resolution mode. The resolution selection is made by modifying R0 and R1 in the configuration register. TI's older LM75 devices use technology that requires more time to convert data for 9-bit resolution. TMP1075 has a 12-bit resolution where the user selects a different conversion time by changing the R0 and R1 bits in the configuration register. TMP1075 sleeps between measurements to save power. TMP1075 provides the best conversion time results when comparing the devices. Figure 6-1 shows a diagram detailing the wait time before a new temperature occurs.

Figure 6-1 Conversion Time