STMicroelectronics TS2431BILT

Overview

TS2431BILT from STMicroelectronics is an adjustable precision shunt voltage reference IC with 0.5% initial accuracy at 25 °C, 2.5–24 V programmable output, ±35 mV total V_REF deviation over –40 to +105 °C, 0.75 Ω dynamic impedance, and 1–100 mA sink current capability. It serves as a stable voltage reference in feedback loops of isolated DC-DC converters and battery charger control circuits.

For engineers reviewing the TS2431BILT datasheet, TS2431BILT pinout, TS2431BILT application, or TS2431BILT equivalent, key selection criteria include temperature coefficient (50–100 ppm/°C), cathode-to-anode voltage range (V_REF to 24 V), off-state leakage (<500 nA), wide-band noise (300 nV/√Hz), and SOT23-3L thermal resistance (R_thja = 340 °C/W).

Technical Context

The TS2431BILT implements a two-terminal shunt topology with internal bandgap reference and error amplifier, enabling precise regulation via external resistor divider between cathode and reference pins. Its operation requires no external capacitor for stability across load and line variations within specified current and voltage ranges.

It delivers guaranteed performance across industrial temperature (–40 to +105 °C) with 100% production-tested V_REF at 25 °C and correlated limits over full range. The device supports both V_KA = V_REF and V_KA > V_REF configurations per Figure 4 and Figure 11 of the datasheet.

Key Specifications

Pinout & Package

TS2431BILT is housed in a standard SOT23-3L surface-mount package (JEDEC TO-236AB), optimized for space-constrained PCB layouts and compatible with automated assembly processes. Thermal resistance values are R_thjc = 110 °C/W and R_thja = 340 °C/W.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar shunt voltage reference applications.

Compared with TL431ACDBVR and MAX6008AEUR+T, TS2431BILT uniquely balances 0.5% accuracy, 24 V programmability, and industrial temperature stability-making it optimal for cost-sensitive yet precision-demanding adjustable reference designs.

Availability

TS2431BILT is available at Aetrix Electronics and suitable for isolated flyback SMPS, battery charger feedback, and industrial sensor signal conditioning requiring stable component supply across extended temperature ranges and multi-year production cycles.

Supply support for TS2431BILT 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 microcontrollers, power ICs, analog chips, and MEMS sensors for automotive, industrial, and consumer markets.

The TS2431 belongs to ST's precision analog reference product line, engineered specifically for high-reliability industrial and power management applications demanding guaranteed temperature stability and long-term parametric consistency.

FAQ

What is the minimum cathode current required for regulation at –40 °C?

The TS2431BILT requires ≥1 mA cathode current to maintain regulation across its full industrial temperature range (–40 to +105 °C), as specified in Table 3 of the datasheet. At 25 °C, the minimum is lower (0.3–0.8 mA), but design must ensure ≥1 mA under worst-case cold conditions to guarantee V_REF accuracy and stability.

Can TS2431BILT replace TL431 in existing designs without layout changes?

Yes-TS2431BILT uses the same SOT23-3L footprint and pinout (Cathode, Anode, REF) as TL431, enabling direct drop-in replacement. However, due to tighter 0.5% initial tolerance and lower dynamic impedance, system-level validation of loop stability and transient response is recommended before full deployment.

How does the reference input current (I_REF) vary with temperature?

I_REF ranges from 0.5–2.5 µA at 25 °C and increases to ≤3 µA over –40 to +105 °C (Table 2). This low, predictable variation minimizes gain error in resistor-divider networks and supports use of high-value divider resistors (>100 kΩ) without significant self-heating or bias current error.

What is the maximum power dissipation in SOT23-3L at +105 °C ambient?

At T_amb = +105 °C, maximum power dissipation is limited to 120 mW, calculated from P_D = (T_jmax – T_amb) / R_thja = (150 – 105) / 340 ≈ 0.132 W. Derating is required above 25 °C ambient; full 360 mW rating applies only at T_amb = 25 °C per absolute maximum ratings table.