Texas Instruments TMP6131DECT

Overview

TMP6131DECT from Texas Instruments is a silicon-based linear positive temperature coefficient (PTC) thermistor in a 0402 X1SON (DEC) package, delivering 10-kΩ nominal resistance at 25°C with ±1% tolerance over 0°C to 70°C, 6400 ppm/°C TCR at 25°C, and –40°C to +125°C operating range. It enables direct voltage-divider or current-source temperature sensing in space-constrained thermal monitoring applications such as motor control and display backlight compensation.

For engineers reviewing the TMP6131DECT datasheet, TMP6131DECT pinout, TMP6131DECT application, or TMP6131DECT equivalent, key selection considerations include its linear R-T response eliminating NTC linearization circuitry, fast 0.6-s thermal response in stirred liquid, built-in fail-safe behavior under short-circuit conditions, and compatibility with ratiometric ADC interfaces using shared V_BIAS/V_REF.

Technical Context

The TMP6131DECT operates as a two-terminal passive resistive sensor whose resistance increases linearly with temperature due to its silicon PTC structure. Its electrical behavior is defined by a fourth-order polynomial R-T model, with bias-dependent characteristics: resistance varies with applied voltage (0–5.5 V) and sense current (0–400 µA), requiring recalibration of the R-T table when RBIAS or VBIAS changes.

Unlike NTCs, it exhibits monotonic, predictable sensitivity across –40°C to +125°C (X1SON package limit), with TCR stability of ±0.2% typical across temperature and minimal self-heating due to low thermal mass and <5.5-V max operating voltage. Its fail-safe operation arises from inherent PTC behavior: rising resistance under overtemperature or short-to-supply conditions limits power dissipation.

Key Specifications

Pinout & Package

The TMP6131DECT is housed in a 2-pin 0402 X1SON (DEC) package measuring 1.00 mm × 0.60 mm with exposed pad for thermal conduction. Pin 1 is the negative terminal (–); Pin 2 is the positive terminal (+). Polarity must be observed: + must be biased at higher potential than – for proper PTC operation and fail-safe behavior.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar linear thermistor applications.

Compared with TMP6131DECT, TMP6132DECT offers improved initial accuracy at higher cost and tighter test requirements, while TMP6331DECT shifts the impedance operating point to reduce bias current-both retain identical package, thermal response, and fail-safe behavior but serve distinct precision and power trade-offs.

Availability

TMP6131DECT is available at Aetrix Electronics and suitable for motor thermal protection, display backlight compensation, HVAC thermostat sensing, and industrial power supply monitoring requiring stable component supply and long-term calibration integrity.

Supply support for TMP6131DECT 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

Texas Instruments is a global semiconductor company headquartered in Dallas, Texas, designing analog and embedded processing products for industrial, automotive, and consumer markets.

The TMP61 series was developed to replace NTC thermistors in high-reliability thermal sensing, delivering linearity, fail-safe behavior, and simplified signal conditioning for systems where calibration overhead and thermal instability are critical constraints.

FAQ

What is the maximum operating temperature for the TMP6131DECT?

The TMP6131DECT has a maximum operating temperature of +125°C when used in the DEC (X1SON) package. This rating is specified in the Recommended Operating Conditions table and reflects thermal limits for the 0402 footprint variant. Exceeding this temperature may cause irreversible drift or parametric shift. The device remains functional up to +150°C in DYA and LPG packages, but TMP6131DECT is exclusively rated to +125°C per TI's SBOS921F datasheet revision November 2023.

Does the TMP6131DECT require external linearization circuitry?

No, the TMP6131DECT does not require external linearization circuitry. Its silicon-based PTC structure delivers inherently linear resistance vs. temperature behavior across –40°C to +125°C, enabling direct use in voltage-divider or current-source configurations without parallel resistors or complex polynomials. This eliminates the need for midpoint calibration or lookup tables typically required with NTC thermistors-simplifying both hardware design and firmware implementation for the TMP6131DECT.

How is the fail-safe behavior implemented in the TMP6131DECT?

The TMP6131DECT implements fail-safe behavior through its intrinsic positive temperature coefficient: during a short-to-supply event, rising current causes self-heating, which increases resistance and naturally limits further current flow-preventing thermal runaway. This contrasts with NTC devices, which decrease resistance under self-heating and enter destructive positive feedback. The TMP6131DECT's fail-safe is passive, requires no additional components, and is guaranteed across its full operating range without firmware intervention.

Can the TMP6131DECT be used with a 3.3-V microcontroller ADC?

Yes, the TMP6131DECT is fully compatible with 3.3-V microcontroller ADCs. Its maximum operating voltage is 5.5 V, and recommended bias voltage (V_SNS) spans 0–5.5 V. When used in a ratiometric voltage-divider configuration-with V_BIAS tied to the ADC's reference voltage-the TMP6131DECT achieves supply-tolerance cancellation, delivering stable readings even with 3.3-V rail variation. Typical bias currents of 100–200 µA ensure minimal self-heating and full-scale utilization of the ADC's dynamic range.

What is the thermal response time of the TMP6131DECT in still air?

The TMP6131DECT has a thermal response time of 3.2 seconds to reach 63% of final resistance value when transitioning from 25°C to 70°C in still air, as measured per JEDEC JESD51-2 standards. This value is specific to the DEC (X1SON) package and reflects its small 1.00 mm × 0.60 mm footprint and low thermal mass. In stirred liquid, response improves to 0.6 s-making the TMP6131DECT suitable for both ambient air monitoring and rapid-contact thermal event detection.