1. TL1431IZT Substitution Conclusion The TL1431IZT can directly replace the TL431CLPRAG in terms of core functionality, package, and fundamental electrical parameters. Both are adjustable shunt voltage references, sharing identical output voltage range (2.5V to 36V), output current (100mA), and cathode operating current (1mA). They are also physically compatible in package (TO-92 series). The differences lie in accuracy and temperature coefficient: the TL1431IZT offers higher initial accuracy (±0.4% vs. ±2.2%), providing an output voltage closer to the nominal value at room temperature, which is beneficial for improving system initial accuracy. However, it has a worse temperature coefficient (100ppm/°C vs. 50ppm/°C typical), leading to greater output voltage drift over temperature across a wide operating range. This may affect stability in high- or low-temperature environments. If the application demands high room-temperature accuracy and operates within a narrow temperature range, the TL1431IZT can be prioritized as a substitute. If the application is more sensitive to stability across the full temperature range, the impact of temperature drift must be evaluated for acceptability.