TL431ACLPRE3 Replacement: LM431BCZXA, AS431IAZTR-G1

Original Part

TL431ACLPRE3

Texas Instruments

Shunt Voltage Reference IC Adjustable 2.495V 36 VV ±1% 100 mA TO-92-3

Alternative Part

LM431BCZXA

onsemi

Shunt Voltage Reference IC Adjustable 2.495V 36 VV ±1% 100 mA TO-92-3

AS431IAZTR-G1

Diodes Incorporated

Shunt Voltage Reference IC Adjustable 2.5V 36 VV ±0.5% 100 mA TO-92

1. LM431BCZXA Substitution Conclusion The LM431BCZXA matches the original TL431ACLPRE3 in key parameters such as output voltage range (2.495V–36V), output current (100mA), tolerance (±1%), and package, making it a candidate for direct substitution. Differences lie in cathode current (1 mA vs. the original 600 µA) and temperature coefficient (50 ppm/°C typical vs. unspecified in the original). The higher cathode current of the LM431 requires a larger minimum operating current, which may increase power consumption and affect stability in low-power or battery-operated circuits. On the other hand, the defined temperature coefficient offers better thermal stability, benefiting applications sensitive to ambient temperature variations. Overall, if the application circuit can accommodate the higher cathode current and would benefit from temperature compensation, the LM431BCZXA is a viable substitute; however, its performance should be carefully verified in low-current designs.

2. AS431IAZTR-G1 Substitution Conclusion The AS431IAZTR-G1 is comparable to the original TL431ACLPRE3 in output voltage range (2.5V–36V) and output current (100mA), with compatible packaging and improved tolerance (±0.5% vs. the original ±1%), making it an enhanced alternative from an accuracy standpoint. Key differences include reference voltage (2.5V vs. 2.495V), tighter tolerance, and cathode current (50 µA vs. 600 µA). The slight variation in output voltage may introduce system error in precision reference applications, requiring circuit calibration. The higher tolerance improves overall performance reliability, while the significantly lower cathode current reduces power consumption, making the AS431 more suitable for energy-efficient or portable devices. In summary, if the application is not sensitive to absolute voltage or can be adjusted, the AS431IAZTR-G1 serves as an efficient replacement offering better accuracy and power efficiency.

Analysis ID: 9670-4119000

Based on part parameters and for reference only. Not to be used for procurement or production.