GS8591-TR 4.5MHZ Zero-Drift CMOS Rail-to-Rail IO Opamp with RF Filter

Product Overview: GS8591-TR vs. LMP2021MFE/NOPB

The GS8591-TR is a high-precision, low-noise, low-offset CMOS operational amplifier designed for applications requiring accurate signal amplification, such as sensor interfaces, instrumentation, and medical electronics. It directly competes with the LMP2021MFE/NOPB from Texas Instruments, which is known for its ultra-low offset and low bias current. While both devices are high-precision amplifiers, the GS8591-TR delivers comparable or better performance in multiple key metrics while maintaining design and cost advantages.

Input Offset Voltage and Offset Drift

The GS8591-TR features an extremely low input offset voltage of 5 μV (typical), matching or outperforming the LMP2021MFE/NOPB, which also specifies a typical offset of 5 μV. Both devices ensure excellent DC accuracy; however, the GS8591-TR offers tight offset voltage distribution across production, improving system-level precision and reducing the need for external calibration in cost-sensitive designs.

Moreover, the GS8591-TR maintains excellent temperature drift characteristics (≤0.05 μV/°C), providing superior long-term and thermal stability in comparison to typical values of 0.04–0.1 μV/°C for the LMP2021. This enables the GS8591-TR to maintain consistent performance over wide operating temperature ranges.

Noise Performance

The GS8591-TR offers outstanding low-noise characteristics, with a typical input voltage noise density of 8 nV/√Hz at 1 kHz, making it ideal for precision low-frequency applications. While the LMP2021MFE/NOPB also achieves similar low-noise levels, the GS8591-TR implements an optimized CMOS architecture that ensures minimal 1/f noise and excellent overall SNR, without introducing chopper artifacts or ripple that can impact sensitive analog systems.

Power Consumption and Supply Range

Designed for modern low-power systems, the GS8591-TR operates at a typical quiescent current of 750 μA, offering excellent balance between precision and efficiency. The LMP2021MFE/NOPB draws a slightly higher quiescent current of 1.1 mA, which can be a concern in portable or battery-powered systems.

Both amplifiers support wide supply voltages, with the GS8591-TR specified for 2.2 V to 5.5 V operation, versus 2.7 V to 5.5 V for the LMP2021. This makes the GS8591-TR more flexible in low-voltage applications such as modern ADC front-ends, wearable electronics, and IoT nodes.

Rail-to-Rail Performance and Output Drive

The GS8591-TR provides rail-to-rail output and near rail-to-rail input operation, maximizing dynamic range and minimizing headroom requirements. It also features strong output drive capability, allowing it to drive capacitive loads and resistive sensors directly without additional buffers.

The LMP2021MFE/NOPB offers rail-to-rail output but lacks true rail-to-rail input capability, limiting input range slightly in single-supply systems. The GS8591-TR therefore supports more flexible front-end interfacing and simplifies circuit design when operating near supply rails.

Package, Pinout, and Layout Compatibility

The GS8591-TR is housed in a compact SOT-23-5 (SOT23-5L) package, directly matching the LMP2021MFE/NOPB, ensuring pin-to-pin compatibility and drop-in replacement capability for existing designs. This facilitates BOM consolidation and second-source qualification for cost-sensitive or supply chain-optimized projects.

EMI Robustness and Stability

The GS8591-TR features built-in EMI-hardened architecture and is optimized for capacitive load stability, which enhances robustness in noisy industrial or automotive environments. Compared to the LMP2021MFE/NOPB, the GS8591-TR offers greater immunity to RF and switching interference, reducing layout constraints and improving long-term reliability.

Conclusion

The GS8591-TR provides a high-performance, low-offset, and low-noise solution that rivals or surpasses the LMP2021MFE/NOPB in most key specifications. With lower power consumption, broader input range, enhanced EMI immunity, and full rail-to-rail performance, it is ideally suited for modern analog applications that demand accuracy, efficiency, and robustness. Its pin-compatible SOT-23-5 footprint also ensures seamless integration into existing designs, making the GS8591-TR a superior and cost-effective alternative for designers seeking precision without compromise.