Original Part
Alternative Part
1. AD621BRZ-RL Substitution Conclusion
The AD621BRZ-RL can serve as a substitute for the INA118UBG4, but several key differences must be considered. Notably, the AD621BRZ-RL has a higher minimum supply voltage of 4.6V (vs. 2.7V for the INA118), a higher input offset voltage of 50µV (vs. 10µV), and a higher quiescent current of 900µA (vs. 350µA). Direct substitution is not feasible if the original system operates below 4.6V. The increased offset voltage will degrade DC accuracy, which may impact high-precision measurement applications. The higher quiescent current also raises system power consumption, making it unsuitable for power-sensitive designs. However, if the system supply voltage exceeds 4.6V and the accuracy and power consumption are acceptable, the AD621BRZ-RL can be a functional replacement due to its lower input bias current (500pA vs. 1nA) and higher output drive capability (18mA vs. 12mA), provided the package is compatible.
2. AD621ARZ-RL Substitution Conclusion
The AD621ARZ-RL can also replace the INA118UBG4, though its applicability is more limited compared to the AD621BRZ-RL. Key differences are similar, including a higher minimum supply voltage (4.6V vs. 2.7V) and higher quiescent current (900µA vs. 350µA). Moreover, the input offset voltage of the AD621ARZ-RL is further increased to 75µV, which is significantly higher than the INA118’s 10µV. Beyond the constraints on supply voltage and power consumption, its reduced DC accuracy restricts its use to applications where offset error is not critical, such as AC signal conditioning at higher gains. If the application allows for higher supply voltage and power dissipation, and has relaxed precision requirements, the AD621ARZ-RL can be substituted based on its pin compatibility and comparable bandwidth and slew rate.
Analysis ID: 1E5B-A3AA000
Based on part parameters and for reference only. Not to be used for procurement or production.
SkyChip © 2026, Email: sales@skychip.com