LMT85LPG - Texas Instruments

LMT85LPG Frequently Asked Questions (FAQs)

• What is the recommended PCB layout for optimal thermal performance?
  Texas Instruments recommends a 2-layer PCB with a solid ground plane on the bottom layer and a thermal relief pattern around the device to minimize thermal resistance. A 4-layer PCB with a dedicated thermal layer can also be used for even better thermal performance.
• How do I calibrate the LMT85LPG for high-accuracy temperature measurements?
  The LMT85LPG has a built-in calibration mechanism that can be accessed through the CAL_MODE pin. By setting CAL_MODE high, the device enters calibration mode, and the user can adjust the offset and gain registers to achieve high-accuracy temperature measurements.
• What is the maximum cable length for the digital interface, and how do I ensure signal integrity?
  The maximum cable length for the digital interface is dependent on the clock frequency and the signal quality. As a general guideline, Texas Instruments recommends keeping the cable length below 10 inches (25 cm) for clock frequencies up to 400 kHz. To ensure signal integrity, use a twisted pair cable with a characteristic impedance of 100 ohms, and terminate the lines with a 100-ohm resistor at the receiving end.
• How do I handle the power-on reset (POR) and brown-out reset (BOR) in my system design?
  The LMT85LPG has a built-in POR and BOR circuitry that resets the device during power-up and brown-out conditions. To handle these events, the system designer should ensure that the device is properly powered up and that the reset signal is properly debounced and synchronized with the system clock.
• What is the recommended power supply decoupling for the LMT85LPG?
  Texas Instruments recommends using a 10-uF ceramic capacitor in parallel with a 1-uF ceramic capacitor, both placed as close as possible to the device's power pins. This decoupling scheme helps to filter out noise and ensure stable operation of the device.