STMicroelectronics TS321AILT

Overview

TS321AILT from STMicroelectronics is a low-power single bipolar operational amplifier in SOT23-5 package, designed for cost-sensitive space-constrained applications. It delivers 2 mV max input offset voltage (A-grade), 500 µA supply current, and rail-to-rail output swing from 0 V to 3.5 V (V_CC = 5 V), enabling use in single-supply sensor signal conditioning and portable battery-powered systems.

For engineers reviewing the TS321AILT datasheet, TS321AILT pinout, TS321AILT application, or TS321AILT equivalent, key selection criteria include input offset voltage grade (A vs standard), capacitive load stability, common-mode input range extending to ground, and thermal performance in SOT23-5 at extended temperature (−40 °C to +125 °C).

Technical Context

The TS321AILT uses a bipolar input stage with PNP differential pair, enabling rail-to-rail common-mode input down to ground and stable operation with capacitive loads up to 100 pF. Its gain-bandwidth product is 0.8 MHz and phase margin is 60°, ensuring unity-gain stability without external compensation.

It operates across a wide supply range: 3–30 V single supply or ±1.5–±15 V dual supply. Input bias current is 20 nA (typ), and large-signal voltage gain exceeds 50 V/mV at V_CC = 15 V with 2 kΩ load - sufficient for precision DC amplification and active filtering.

Key Specifications

Pinout & Package

SOT23-5 plastic surface-mount package (ECOPACK® compliant), 2.9 mm × 2.8 mm footprint, 1.3 mm height, thermal resistance R_thJA = 250 °C/W.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar single-channel low-power op amp applications.

Compared with LM321DR and MCP6001T-I/OT, TS321AILT uniquely balances A-grade offset (2 mV), SOT23-5 footprint, 0.8 MHz bandwidth, and bipolar input robustness - making it optimal for space-limited industrial signal chains requiring moderate speed and precision without rail-to-rail input.

Availability

TS321AILT is available at Aetrix Electronics and suitable for temperature sensing, battery monitoring, industrial current loop receivers, and low-power smoke detector signal chains requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for TS321AILT 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, Switzerland, designing and manufacturing analog, MCU, power, and sensor solutions for industrial, automotive, and consumer markets.

The TS321 belongs to ST's general-purpose bipolar op amp product line, engineered for cost-effective, space-efficient signal conditioning in industrial and portable equipment where precision, low power, and extended temperature operation intersect.

FAQ

What is the maximum capacitive load the TS321AILT can drive without oscillation?

The TS321AILT is specified stable with ≥100 pF capacitive load under unity-gain conditions, per its 60° phase margin and internal compensation. Driving >100 pF (e.g., long cables or high-C_IN ADCs) requires an isolation resistor (≥100 Ω) between output and load to maintain stability, as confirmed in Figure 3 and Section 4.3 of the datasheet.

Does the TS321AILT support true rail-to-rail input?

No - the TS321AILT features a ground-sensing input stage (common-mode range includes 0 V) but does not support rail-to-rail input. Its input common-mode range extends from 0 V to (V_CC − 1.5) V at 25 °C, meaning it cannot accept signals within 1.5 V of the positive rail without degradation in CMRR or offset.

How does the TS321AILT differ from the standard TS321ILT?

The TS321AILT is the A-grade version: it guarantees 2 mV max input offset voltage (vs. 4 mV for TS321ILT) and 3 mV max over full temperature range (vs. 5 mV). All other specifications - supply current, bandwidth, package, and pinout - are identical. Marking code "K402" distinguishes it on tape-and-reel packaging.

Can the TS321AILT operate from a 3.3 V supply?

Yes - the TS321AILT is fully specified from 3 V to 30 V single supply. At V_CC = 3.3 V, output swing is guaranteed ≥0 V to 2.0 V (min), input common-mode range is 0 V to 1.8 V, and supply current remains ~500 µA. These values are derived from interpolation of Table 3 and Table 2 in the datasheet.