(like the Abigail, CX-Pro, or JCally JM6) is heating up or behaving poorly, you aren't alone. Here is the breakdown of why this happens and how to handle it. 1. The "Heat" Problem: Why it Happens Power Mismatch: Users have reported that the CX31993 (often paired with a
A drop from 55°C to 35°C under load.
The chip itself, when operating within limits, should feel slightly warm (35-45°C case temperature). If it’s too hot to hold (>60°C), you are violating one or more of these parameters. cx31993 datasheet fix hot
The DAC chip is a common budget-friendly component often paired with the MAX97220 amplifier in portable USB-C dongles. While a formal, public "datasheet" from the manufacturer (Conexant/Synaptics) is notoriously difficult to find, community documentation and real-world testing highlight a recurring issue where these devices run excessively hot and produce static. Why it gets "Hot"
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: (like the Abigail, CX-Pro, or JCally JM6) is
Some cheap AliExpress clones have defective EEPROMs that fail to put the chip into standby mode when idle. The CX31993 is supposed to draw <1mA when muted, but a bad firmware flash keeps the amp biased to Class A.
Many cheap dongles come in plastic casings. Plastic is an insulator. If your chip runs hot: The "Heat" Problem: Why it Happens Power Mismatch:
utilizes a Class G amplifier, which is efficient but requires managing power effectively when driving headphones. When playing high-resolution audio (32bit/384kHz) or driving low-impedance, power-hungry headphones, the chip pulls significant power, converting the excess into heat, especially in such a small enclosure. 2. Lack of Thermal Dissipation
This paper addresses a critical discrepancy between the published thermal characteristics in the CX31993 datasheet and empirical observations during standard operation. Users have reported significant thermal events—colloquially referred to as "hot" instances—where the device exceeds junction temperature limits under nominal load conditions. This document analyzes the power dissipation characteristics of the CX31993, identifies the root cause of the thermal mismanagement as an erroneous datasheet specification regarding thermal resistance ($R_\theta JA$), and proposes a formal datasheet fix. The proposed correction redefines the thermal design parameters, ensuring reliable integration and preventing premature thermal shutdown or component degradation.
Since there is no official firmware "patch" for a hardware thermal issue, users rely on these practical workarounds: