SLOA318 November 2021 TMP421-Q1 , TMP451-Q1 , TMP61-Q1
LIDAR systems need multiple temperature sensors in several locations due to redundancy and diversity requirements to achieve ASIL ratings. This temperature monitoring design challenge can be solved efficiently several ways using TI’s automotive grade temperature sensors. The combination of two analog sensors, two of TI’s TMP6 thermistors or a TMP6 thermistor and a TMP235-Q1 device, helps achieve a low-cost design. Using TI's automotive grade remote and local temperature sensors allows designers to take advantage of any built-in thermal transistors while also minimizing the number of external components.
Table 4-1 displays a comparison of the different options presented in this document.
| Option | Cost | Diversity | MCU, Processor, or Other Resources Needed | Ability to Utilize Integrated Thermal Transistors |
|---|---|---|---|---|
| TMP6x-Q1 thermistors | Lower | Different package options Difference devices | ADC or ADCs Biasing circuit | No |
| Automotive analog temperature sensor ICs | Middle | Different package options Different devices Different gain | ADC or ADCs | No |
| Automotive remote temperature sensors | Higher | Different package options Different transistors (NPN or PNP) | I2C bus or buses | Yes |
| Higher | Different package options Different devices Different transistors (NPN or PNP) | I2C bus or buses | Yes |