USB-DUX

Description: The input range of the USB-DUX sigma board (+/-1.35V) is compatible with the output voltage range of the LM35 temperature sensor. Ground (GND) is accessible on multiple pins of the HD connector, allowing selection of the most convenient pins for soldering. Resistor R5 should be placed near the D connector, such as within the backshell, to serve as a termination and to mitigate oscillations. To facilitate the measurement of negative temperatures, a 100K resistor should be connected between pins 16 and 31 (-5V).

The USB-DUX sigma board is designed to interface seamlessly with the LM35 temperature sensor, which provides a linear output voltage proportional to the temperature in degrees Celsius. The specified input voltage range of +/-1.35V ensures that the board can accurately process the output of the LM35, which typically operates within a similar voltage range.

The HD connector on the board offers multiple ground pins, enhancing flexibility during the assembly process. This allows for optimal placement of ground connections, minimizing potential noise and improving signal integrity. The careful selection of ground pins can significantly affect the performance of the circuit, especially in sensitive applications.

The placement of resistor R5 is critical; it should be soldered close to the D connector. This positioning acts as a termination resistor, which is essential for reducing reflections and preventing oscillations in high-frequency signals. Proper termination is crucial for maintaining signal quality and ensuring reliable operation of the overall system.

For applications requiring the measurement of negative temperatures, the inclusion of a 100K resistor between pins 16 and 31 is necessary. This configuration allows the circuit to extend its measurement capabilities into the negative temperature range, which is particularly useful in various environmental monitoring applications. The careful integration of this resistor ensures that the LM35 can provide accurate readings even when temperatures drop below zero degrees Celsius.

Overall, the design considerations outlined here highlight the importance of careful component placement and selection in achieving optimal performance in temperature measurement applications using the USB-DUX sigma board and the LM35 sensor.The input range of the USB-DUX sigma board (+/-1. 35V) matches perfectly the output voltage range of the LM35. GND is available on many pins on the HD connector (check out the pinout ) so that you can choose the ones which are easiest to solder to. R5 should be soldered close to the D con nector (e. g. inside of the backshell) which acts as a termination and prevents oscillations. To be able to measure negative temperatures connect a 100K resistor between pins 16 and 31 (-5V).