have successfully dropped temperatures by 15-20°C by applying small VRM heatsinks and thermal pads directly to the dongle's shell. Improve Airflow
Because Conexant’s assets changed hands over the years (eventually landing under Synaptics ), an official public-facing datasheet can be incredibly elusive. Most implementation details must be reverse-engineered or gathered from manufacturer reference designs.
The CX31993 is stable driving up to 300Ω (per datasheet output voltage swing). Using: cx31993 datasheet fix hot
For desktop use, attaching a tiny passive aluminum heatsink to the DAC body can significantly lower temperatures. Understanding the CX31993 Specs (Summary) Based on commonly available technical specifications: Specification Interface Type-C to 3.5mm Sampling Rate 32bit / 384kHz SNR DNR THD+N 0.0003% (95dB) Output Thrust Amp Type Conclusion
Increase the USB buffer size. This reduces the number of interrupts the DAC has to process. The CX31993 is stable driving up to 300Ω
Cut a tiny piece of high-conductivity thermal pad (0.5mm thickness is usually ideal) and place it directly on top of the CX31993 chip.
Initial investigations suggested potential silicon defects. However, further analysis indicates that the root cause lies in the misinterpretation of thermal design parameters provided in the official datasheet. Specifically, the thermal resistance values listed for the package do not align with the measured performance on standard printed circuit board (PCB) layouts. This paper outlines the experimental verification of this anomaly and details the necessary "fix" to the datasheet to align engineering specifications with physical reality. This reduces the number of interrupts the DAC has to process
If a CX31993 is getting hot, the issue is almost never a design problem with the chip itself. Instead, it stems from its implementation in a specific dongle or the environment in which it's used. The primary engineering causes are:
-based device is running hot, several software and hardware adjustments can mitigate the issue: