STMicroelectronics TSZ121ILT

Overview

TSZ121ILT from STMicroelectronics is a single-channel, rail-to-rail input/output precision operational amplifier featuring 5 µV max input offset voltage at 25 °C and 8 µV over –40 °C to +125 °C, 400 kHz gain bandwidth product, 1.8–5.5 V supply range, and 40 µA max supply current at 5 V. It serves as a low-drift, micropower signal conditioning front-end in battery-powered sensor interfaces.

For engineers reviewing the TSZ121ILT datasheet, TSZ121ILT pinout, TSZ121ILT application, or TSZ121ILT equivalent, this chopper-stabilized op-amp delivers verified zero-drift performance, EMI robustness (91 dB at 2.4 GHz), and rail-to-rail operation in SC70-5 - critical for high-accuracy analog acquisition in space- and power-constrained designs.

Technical Context

The TSZ121ILT employs a 400 kHz chopper-stabilized architecture that continuously corrects input offset and 1/f noise by modulating the input signal, amplifying it, then demodulating and filtering-resulting in <10 nV/°C drift and sub-1 µVpp 0.1–10 Hz noise. Its CMOS input stage enables ultra-low bias current (≤300 pA over temperature) and high common-mode rejection (110–136 dB).

It operates across 1.8–5.5 V with rail-to-rail input common-mode range (V_CC– –0.1 V to V_CC+ +0.1 V) and output swing within 30 mV of rails at 25 °C. The internal 400 kHz chopping clock synchronizes offset correction without external components, eliminating need for calibration in medical-grade or portable instrumentation.

Key Specifications

Pinout & Package

TSZ121ILT is packaged in SC70-5 (SOT-353), a 1.25 mm × 1.65 mm surface-mount package with 0.65 mm pitch. The exposed pad is not electrically connected and may be left floating or tied to V_CC–.

Key Features

Applications

Equivalent & Alternatives

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

Compared with OPA333AIDBVR and MCP6V81T-E/OT, TSZ121ILT uniquely balances ultra-low drift (10 nV/°C), micropower operation (40 µA), and usable bandwidth (400 kHz) - making it optimal for autonomous, wide-temperature sensor nodes where calibration infrastructure is absent.

Availability

TSZ121ILT is available at Aetrix Electronics and suitable for portable medical devices, battery-powered gas sensors, wearable diagnostics, and industrial thermopile interfaces requiring stable component supply across extended temperature and long lifecycle programs.

Supply support for TSZ121ILT 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 sensor solutions for industrial, automotive, and consumer markets.

TSZ121ILT belongs to the TSZ12x zero-drift precision op-amp family, engineered specifically for ultra-low-offset, micropower signal conditioning in battery-constrained, high-reliability applications such as portable healthcare and environmental monitoring.

FAQ

What is the maximum capacitive load the TSZ121ILT can drive while maintaining stability?

The TSZ121ILT is unity-gain stable up to 100 pF with 10 kΩ series resistance, as validated in Figure 29 (overshoot vs. load capacitance). Driving >100 pF directly causes peaking and potential oscillation; for larger loads, add a 10–100 Ω isolation resistor between output and capacitance, or use a dedicated buffer stage.

Does the TSZ121ILT require external clocking or configuration pins for chopper operation?

No. The chopper stabilization runs autonomously at a fixed 400 kHz internal clock frequency; no external timing components, configuration pins, or user intervention are needed. This simplifies PCB layout and eliminates clock-related EMI concerns in sensitive analog sections.

Can the TSZ121ILT operate from a single 1.8 V supply with rail-to-rail input and output?

Yes. TSZ121ILT is fully specified from 1.8 V to 5.5 V. At 1.8 V, it maintains rail-to-rail input (–0.1 V to +1.9 V) and output swing within 30 mV of each rail at 25 °C, enabling full-scale signal utilization in ultra-low-voltage energy-harvesting systems.

How does the TSZ121ILT handle input overvoltage conditions beyond its absolute maximum ratings?

Per Table 1, differential input voltage must not exceed ±V_CC. Figure 32–35 show recovery from ±1 V overvoltage transients in <400 µs with no latch-up or parametric shift. Internal ESD diodes clamp to rails, but sustained overvoltage requires external series resistors to limit current to <10 mA per pin.