Texas Instruments TMP6431QDYATQ1

Overview

TMP6431QDYATQ1 from Texas Instruments is an automotive-grade silicon linear thermistor with positive temperature coefficient (PTC), 47-kΩ nominal resistance at 25 °C (±1% tolerance over 0 °C to 70 °C), 6400 ppm/°C TCR at 25 °C, and fast 0.6 s thermal response in stirred liquid. It operates from –40 °C to 150 °C in the SOT-5X3 (DYA) package and serves as a precision temperature sensing element in motor control and on-board charger thermal monitoring circuits.

For engineers reviewing the TMP6431QDYATQ1 datasheet, TMP6431QDYATQ1 pinout, TMP6431QDYATQ1 application, or TMP6431QDYATQ1 equivalent, key selection considerations include its AEC-Q100 Grade 0 qualification, linear R–T behavior eliminating NTC linearization circuitry, ±0.2% typical TCR tolerance across temperature, and compatibility with ratiometric voltage-divider or precision current-source biasing architectures.

Technical Context

The TMP6431QDYATQ1 implements a monolithic silicon PTC structure where doping and active region geometry define both R25 and TCR. Its resistance increases linearly with temperature-unlike NTCs-enabling direct polynomial or lookup-table conversion without external linearization components. The device requires proper polarity: pin 2 (+) must be at higher potential than pin 1 (–) to ensure stable operation and built-in fail-safe behavior during overtemperature events.

It supports two primary biasing topologies: ratiometric voltage divider (with 47-kΩ bias resistor and shared V_BIAS/V_REF) for supply-tolerance cancellation, or constant-current source (up to 100 µA) for full ADC code utilization and 40 mV/°C sensitivity. Thermal response is characterized separately for stirred liquid (0.6 s) and still air (3.2 s), reflecting its low thermal mass and suitability for rapid thermal event detection.

Key Specifications

Pinout & Package

The TMP6431QDYATQ1 is housed in a 2-pin SOT-5X3 (DYA) package measuring 0.60 mm × 1.00 mm, optimized for high-density automotive PCB layouts and thermal coupling to heat sources.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TMP6421QDYATQ1 and TMP6131QDYATQ1, the TMP6431QDYATQ1 provides the highest combination of temperature range (–40 °C to 150 °C), sensitivity (6400 ppm/°C), and baseline resistance (47 kΩ), making it optimal for high-accuracy thermal protection in power-conversion stages where both extended range and resolution are critical.

Availability

TMP6431QDYATQ1 is available at Aetrix Electronics and suitable for motor control thermal monitoring, on-board charger overtemperature protection, and DC-DC converter thermal foldback requiring stable component supply across automotive production lifecycles.

Supply support for TMP6431QDYATQ1 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 specializing in analog and embedded processing technologies, with leadership in precision sensing, power management, and automotive-qualified components.

The TMP64-Q1 product line delivers silicon-based linear thermistors engineered for automotive thermal management systems requiring AEC-Q100 qualification, long-term stability, and elimination of NTC linearization overhead.

FAQ

What is the maximum operating temperature of the TMP6431QDYATQ1?

The TMP6431QDYATQ1 is qualified to AEC-Q100 Grade 0 with a maximum operating temperature of +150 °C in the SOT-5X3 (DYA) package. This rating is validated per JEDEC JESD22-A108 and applies to continuous operation under recommended bias conditions (≤5.5 V, ≤100 µA). The device maintains ±0.2% typical TCR tolerance and <±0.5 °C measurement accuracy across this full range, making TMP6431QDYATQ1 suitable for under-hood power electronics where ambient temperatures exceed 125 °C.

How does the TMP6431QDYATQ1 differ from traditional NTC thermistors?

The TMP6431QDYATQ1 uses a silicon PTC structure delivering linear resistance vs. temperature behavior, whereas NTCs exhibit exponential curves requiring external linearization resistors or complex polynomial math. TMP6431QDYATQ1 achieves ±1% R25 tolerance over 0 °C to 70 °C and 6400 ppm/°C TCR with ±0.2% tolerance-enabling direct voltage-to-temperature conversion using simple lookup tables or second-order polynomials. Its built-in fail-safe behavior also limits current during short-to-rail faults, unlike NTCs which can enter thermal runaway.

What biasing configuration is recommended for highest accuracy with the TMP6431QDYATQ1?

For highest accuracy, Texas Instruments recommends a precision current-source bias (e.g., 100 µA) driving TMP6431QDYATQ1 directly into an ADC input. This yields ~40 mV/°C sensitivity and full utilization of the ADC's code range, minimizing quantization error. When using voltage-divider biasing, match V_BIAS to the ADC's reference voltage (ratiometric configuration) to cancel supply tolerance effects. Both methods require proper PCB layout: minimize trace length to TMP6431QDYATQ1 pins, use ground guard rings, and avoid routing near switching nodes to preserve <±0.5 °C system accuracy.

Does the TMP6431QDYATQ1 require calibration in production?

The TMP6431QDYATQ1 requires no per-unit calibration due to its tight ±1% R25 tolerance (0 °C to 70 °C) and ±0.2% typical TCR tolerance across temperature. System-level accuracy is achieved using TI's Thermistor Design Tool to generate application-specific R–T tables or polynomials based on actual bias voltage, current, and external resistor values. Factory characterization data is laser-trimmed during wafer sort, so TMP6431QDYATQ1 delivers consistent performance across lots without end-of-line trimming-reducing manufacturing test time and cost.

Can the TMP6431QDYATQ1 be used in a comparator-based overtemperature switch?

Yes, the TMP6431QDYATQ1 is explicitly designed for comparator-based thermal switches. Configure it in a voltage divider with a precision 47-kΩ bias resistor and reference voltage; the linear R–T curve produces a monotonic V_TEMP output that crosses comparator thresholds predictably. TI provides design examples with hysteresis networks to prevent chatter near trip points. The built-in fail-safe behavior ensures resistance increases during short-circuit faults-maintaining valid high-side voltage detection and preventing false undervoltage assertions that could disable protection logic in safety-critical systems using TMP6431QDYATQ1.