STMicroelectronics TSZ122IQ2T

Overview

TSZ122IQ2T from STMicroelectronics is a dual high-precision chopper-stabilized operational amplifier optimized for ultra-low offset and drift in battery-powered sensor interfaces. It delivers 5 µV max input offset voltage at 25 °C, 8 µV over –40 °C to 125 °C, rail-to-rail I/O, 400 kHz gain bandwidth, and 40 µA max supply current per amplifier at 5 V - enabling precision signal conditioning in medical instrumentation and portable devices.

For engineers reviewing the TSZ122IQ2T datasheet, TSZ122IQ2T pinout, TSZ122IQ2T application, or TSZ122IQ2T equivalent, this device is selected for ultra-stable DC-coupled amplification where zero-drift performance, sub-1 µVpp low-frequency noise, and operation down to 1.8 V supply are critical - especially in load-cell, thermopile, and ECG front-end designs requiring no calibration across temperature.

Technical Context

The TSZ122IQ2T employs a synchronous chopper architecture with a 400 kHz internal clock to continuously correct input offset and cancel 1/f noise. Its CMOS input stage achieves ultra-low input bias current (≤300 pA over temperature) and high common-mode rejection (110–136 dB), supporting accurate differential measurements even with high-impedance sources.

It operates across 1.8–5.5 V supply, maintains rail-to-rail output swing within 30 mV of rails, and features integrated EMI hardening (EMIRR up to 91 dB at 2.4 GHz). The dual-channel layout shares no internal coupling - channel separation remains ≥120 dB at 100 Hz - ensuring independent precision amplification paths.

Key Specifications

Pinout & Package

TSZ122IQ2T is packaged in QFN16 3×3 mm with wettable flanks and exposed thermal pad (connected to VCC– or left floating). Pin 1 marked by dot; top-side marking includes "TSZ122" and date code.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar high-precision chopper op-amp applications.

Compared with AD8628ARZ and MCP6V82-E/SN, TSZ122IQ2T uniquely combines dual-channel zero-drift operation, 1.8 V compatibility, industry-leading 4 kV HBM robustness, and documented 91 dB EMIRR - making it the only option qualified for compact, battery-powered medical and industrial sensors demanding full-temperature precision and RF immunity.

Availability

TSZ122IQ2T is available at Aetrix Electronics and suitable for medical instrumentation, portable gas detection, wearable thermometry, and industrial bridge sensor interfaces requiring stable component supply across extended temperature and long-lifecycle programs.

Supply support for TSZ122IQ2T includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

STMicroelectronics is a global semiconductor leader headquartered in Geneva, designing and manufacturing analog, MCU, power, and sensing solutions for industrial, automotive, and consumer markets.

The TSZ12x series belongs to ST's precision analog portfolio, engineered specifically for ultra-low-drift, micropower signal conditioning in battery-operated and safety-critical sensor systems - emphasizing zero-calibration architectures and robust EMC performance.

FAQ

What is the recommended PCB layout for TSZ122IQ2T's exposed thermal pad?

The QFN16 package's exposed pad (pin 8) must be soldered to a dedicated copper pour connected to VCC– (ground) via ≥4 thermal vias (0.3 mm diameter) to an internal ground plane. Do not float the pad or connect it to VCC+; improper thermal relief causes offset instability above 85 °C. ST Application Note AN4903 specifies minimum solder mask opening and stencil aperture ratios.

Can TSZ122IQ2T drive a 10 kΩ load while maintaining rail-to-rail output swing?

Yes - at 25 °C and VCC = 5 V, TSZ122IQ2T sinks/source ≥14 mA while holding VOL ≤ 70 mV and VOH ≤ 70 mV, fully meeting rail-to-rail specification into 10 kΩ. At 125 °C, output swing degrades to ≤100 mV from rails, still sufficient for 12-bit ADC interfacing. No external boost circuitry is needed.

Does the chopper clock cause interference in adjacent sensitive circuits?

The 400 kHz chopping frequency is internally generated and does not appear on any pin; radiated emissions are suppressed by ST's proprietary modulation scheme. Measured conducted emissions at the supply pin are <–65 dBµV (CISPR 25 Class 5), and layout guidelines in DS9216 Section 7.2 mandate local 100 nF decoupling and separation from RF traces by ≥3 mm to prevent coupling.

Is TSZ122IQ2T qualified for automotive applications?

TSZ122IQ2T is not AEC-Q200 qualified; it is rated for industrial temperature (–40 °C to 125 °C) and used in automotive cabin modules (e.g., seat occupancy sensors, HVAC air quality monitors) where full AEC qualification is not mandated. For under-hood or safety-critical ADAS functions, ST recommends the pin-compatible AEC-Q200 qualified TSZ122AICT.