KA431AZBU Replacement: TL431BILP, TL431AILPG

Original Part

KA431AZBU

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

Alternative Part

TL431BILP

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Shunt Voltage Reference IC Adjustable 2.495V 36 VV ±0.4% 100 mA TO-92 (TO-226)

TL431AILPG

onsemi

Shunt Voltage Reference IC Adjustable 2.495V 36 VV ±1% 100 mA TO-92 (TO-226)

1. TL431BILP Substitution Conclusion The substitution is fully viable and offers superior performance. The TL431BILP shares identical key electrical parameters with the original KA431AZBU—including reference voltage (2.495V), operating voltage/current ranges, and temperature coefficient. However, a critical improvement is its initial accuracy of ±0.4%, compared to the original’s ±1%. This results in higher absolute accuracy of the reference voltage after substitution, which helps improve overall system voltage‑setting precision or error margin. It serves as a direct upgrade, especially in circuits requiring higher reference voltage accuracy. Although both devices use a TO‑92‑3 package, the TL431BILP is a “Long Body” variant. There may be slight mechanical dimensional differences on the PCB compared to the original TO‑226AA (standard body) footprint. Layout verification for insertion clearance and thermal considerations is recommended, but the electrical pinout and functionality remain fully compatible.

2. TL431AILPG Substitution Conclusion Electrically, the substitution is fully feasible and serves as a pin‑compatible direct replacement, though no accuracy improvement is gained and the package differs. The TL431AILPG matches the original KA431AZBU in nearly all electrical specifications, including ±1% initial accuracy, 50 ppm/°C temperature drift, and all key voltage/current parameters. Thus, its functional performance in the circuit will be identical. The primary distinction lies in the physical package: the TL431AILPG uses a “TO‑92‑3 Long Body” package, which may introduce minor differences in pin spacing and body length compared to the original standard TO‑92‑3 (TO‑226AA). Before substitution, verify that the PCB mounting holes and clearance to adjacent components are suitable. Once mechanically validated, the replacement is seamless with no electrical performance difference.

Analysis ID: CDE5-6CA5000

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