TL431ASA-7 Replacement: NCP431ACSNT1G, NCP432BVSNT1G

Original Part

TL431ASA-7

Diodes Incorporated

Shunt Voltage Reference IC Adjustable 2.495V 36 VV ±1% 100 mA SOT-23-3

Alternative Part

NCP431ACSNT1G

onsemi

Shunt Voltage Reference IC Adjustable 2.5V 36 VV ±1% 40 µA SOT-23-3 (TO-236)

NCP432BVSNT1G

onsemi

Shunt Voltage Reference IC Adjustable 2.5V 36 VV ±0.5% 40 µA SOT-23-3 (TO-236)

1. NCP431ACSNT1G Substitution Conclusion From core functionality and package perspective, NCP431ACSNT1G can substitute TL431ASA-7. Both are adjustable shunt references in SOT-23-3 packages with pin compatibility, identical operating voltage ranges (2.5V/2.495V to 36V), and cathode current capability of 100mA. The primary differences are that NCP431ACSNT1G specifies a typical temperature drift of 50ppm/°C, whereas TL431ASA-7 does not disclose this parameter, giving NCP431 potentially more predictable stability over wide temperature ranges. Additionally, NCP431’s minimum operating current (40µA) is significantly lower than TL431’s (700µA), which benefits low-power designs. However, note that dynamic impedance may increase as current decreases, possibly affecting accuracy and response speed under very light loads. If the application requires low temperature drift and low quiescent current, and can tolerate the slight output voltage shift from 2.495V to 2.5V, substitution is feasible.

2. NCP432BVSNT1G Substitution Conclusion NCP432BVSNT1G improves upon NCP431 with higher accuracy (±0.5% tolerance versus ±1% for TL431), while maintaining the same temperature drift coefficient (50ppm/°C typical), package compatibility, and low operating current (40µA). It offers superior initial accuracy and temperature stability of the reference voltage, making it particularly suitable for analog circuits or ADC reference circuits demanding higher voltage precision. Note, however, that similar to NCP431, its low operating current may be advantageous in high-impedance applications, but dynamic response should be evaluated in high-speed or heavy load‑transient scenarios. If the original system was designed around TL431’s 700µA minimum current, loop stability must be verified after replacement. Overall, NCP432BVSNT1G is a high‑performance drop‑in replacement that enhances system accuracy.

Analysis ID: 5750-3D27000

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