STMicroelectronics TS931BID

Overview

TS931BID from STMicroelectronics is a single-channel rail-to-rail output micropower operational amplifier optimized for low-voltage, battery-powered systems. It operates from 2.7 V to 10 V, consumes only 20 μA typical supply current, delivers 2.95 V output high level at 3 V supply (RL = 100 kΩ), and features 2 mV max input offset voltage (TS931B grade) and 1 pA ultra-low input bias current - enabling precision sensing in portable instrumentation and automotive-grade smoke detectors.

For engineers reviewing the TS931BID datasheet, TS931BID pinout, TS931BID application, or TS931BID equivalent, key selection criteria include micropower operation under 2.7 V, rail-to-rail output swing with <50 mV low-level saturation, CMOS input stage compatibility with high-impedance sensors, and SO-8 packaging for industrial temperature range (-40 °C to +105 °C) compliance.

Technical Context

The TS931BID implements a CMOS-input, rail-to-rail output op-amp architecture with internal compensation for unity-gain stability. Its input stage uses matched P-channel MOSFETs to achieve 1 pA typical input bias current and 2 mV max offset voltage across -40 °C to +105 °C, while the output stage employs complementary push-pull transistors enabling 2.95 V high-level and 10 mV low-level output swing at 3 V supply into 100 kΩ.

It achieves 100 kHz gain-bandwidth product and 50 V/ms slew rate with 65° phase margin (CL = 50 pF), supporting stable closed-loop operation in sensor buffering, pH meter front-ends, and low-power analog signal conditioning where supply rejection (85 dB SVR) and common-mode rejection (85 dB CMR) are critical under varying battery voltage.

Key Specifications

Pinout & Package

TS931BID is housed in an SO-8 package (4.90 mm × 6.00 mm × 1.75 mm), RoHS-compliant and ECOPACK® certified, with standard 1.27 mm pitch and gull-wing leads suitable for automated reflow assembly.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar rail-to-rail micropower op-amp applications.

Compared with LMV321IDBVR and OPA348AIDBVR, TS931BID uniquely balances automotive-grade temperature range, sub-2 mV offset, and true 2.7 V operation with 20 μA consumption - making it irreplaceable in safety-critical, long-life, low-voltage sensor nodes.

Availability

TS931BID is available at Aetrix Electronics and suitable for portable smoke detectors, pH meters, digital kitchen scales, and automotive cabin occupancy sensors requiring stable component supply across extended temperature ranges and multi-year production cycles.

Supply support for TS931BID 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 TS93x series belongs to ST's precision analog portfolio, engineered specifically for ultra-low-power, rail-to-rail signal conditioning in battery-constrained and automotive-qualified applications - emphasizing offset stability, input impedance, and supply flexibility.

FAQ

What is the maximum operating junction temperature for TS931BID?

The TS931BID has a maximum junction temperature (T_j) of 150 °C, validated per absolute maximum ratings in ST's Doc ID 6911 Rev 5. This allows reliable operation in under-hood automotive environments when mounted on PCBs with adequate copper pour and thermal vias, assuming ambient temperatures ≤105 °C and thermal resistance ≤125 °C/W (SO-8 package).

Does TS931BID support dual-supply operation?

No - TS931BID is specified exclusively for single-supply operation from 2.7 V to 10 V, with input common-mode range extending from V_CC− − 0.2 V to V_CC+ − 1.5 V and rail-to-rail output swing referenced to those rails. Dual-supply use (e.g., ±2.5 V) is outside datasheet specifications and may cause undefined behavior or reduced performance.

Can TS931BID drive capacitive loads directly?

TS931BID is unity-gain stable with up to 50 pF capacitive load (per Figure 13–14), but larger loads require isolation resistors (≥100 Ω) in series with the output to prevent peaking or oscillation. Driving >100 pF directly risks instability due to phase margin reduction below 65°, especially with heavy PCB trace capacitance or ADC input capacitance.

Is the SO-8 package of TS931BID lead-free and RoHS compliant?

Yes - TS931BID uses an ECOPACK®-compliant SO-8 package meeting RoHS Directive 2011/65/EU and REACH regulations, with lead-free terminations and halogen-free molding compound. The device marking "931BI" and date code confirm full environmental compliance per ST's public ECOPACK documentation.