1. TL431ACLPG Substitution Conclusion Limited substitution is possible, but key performance degradation must be considered. The primary differences are as follows: First, the initial accuracy decreases from ±0.5% to ±1%, which may lead to a greater deviation in the output voltage reference under normal temperature conditions. This makes it unsuitable for circuits with high accuracy requirements, such as high-precision ADC references or precision voltage regulation. Second, the typical cathode operating current increases from 600µA to 1mA, resulting in slightly higher device power dissipation. In low-power or high-input-voltage designs, thermal performance and efficiency must be re-evaluated. Although it specifies a typical temperature drift coefficient (50ppm/°C) and maintains package compatibility, the reduction in core accuracy parameters remains the primary limitation for direct substitution.