Texas Instruments LMT87QDCKTQ1

Overview

LMT87QDCKTQ1 from Texas Instruments is an AEC-Q100 Grade 0 automotive-qualified analog temperature sensor with ±0.4°C typical accuracy, –13.6 mV/°C output gain, and 5.4 µA quiescent current, operating from 2.7 V to 5.5 V across –50°C to +150°C. It delivers linear, inverse-voltage output with push-pull drive for direct ADC interfacing in powertrain and infotainment systems.

For engineers reviewing the LMT87QDCKTQ1 datasheet, LMT87QDCKTQ1 pinout, LMT87QDCKTQ1 application, or LMT87QDCKTQ1 equivalent, key selection criteria include its SC70-5 package footprint compatibility with LM20/LM35, short-circuit protected output, functional safety documentation support, and low-power cycling capability for battery-operated automotive sensors.

Technical Context

The LMT87QDCKTQ1 implements a CMOS-based thermal diode sensing element with buffered push-pull output stage, enabling monotonic voltage output inversely proportional to temperature without external components. Its transfer function follows a parabolic model (–13.6 mV/°C slope with second-order correction) and maintains ±2.7°C max error over full range without calibration.

It features Class-AB output architecture with ±50 µA sink/source capability, supports capacitive loads up to 1100 pF without series resistance, and exhibits <0.014°C self-heating at 5 V/2 µA load. Power-on time is 0.7 ms, enabling rapid duty-cycled operation in drone and sensor-node applications.

Key Specifications

Pinout & Package

Package: SC70-5 (SOT-5), 2.00 mm × 1.25 mm surface-mount body with exposed die backside connected to GND for thermal conduction.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar analog temperature sensor applications.

Compared with LMT87QDCKTQ1, LMT86QDCKRQ1 offers lower supply voltage operation at reduced sensitivity, while LMT85QDCKRQ1 provides further supply reduction with moderate gain trade-off-both retain AEC-Q100 Grade 0 qualification and SC70-5 compatibility for automotive reuse.

Availability

LMT87QDCKTQ1 is available at Aetrix Electronics and suitable for automotive powertrain systems, infotainment thermal management, and drone battery monitoring requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for LMT87QDCKTQ1 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-grade ICs.

The LMT87-Q1 product line delivers high-accuracy, low-power analog temperature sensors designed specifically for AEC-Q100-compliant automotive subsystems-including powertrain, infotainment, and ADAS thermal monitoring-where calibration-free operation and robust EMC performance are critical.

FAQ

What is the maximum operating temperature range supported by the LMT87QDCKTQ1?

The LMT87QDCKTQ1 supports a full operating temperature range of –50°C to +150°C, with AEC-Q100 Grade 0 qualification covering –40°C to +150°C ambient. Its ±2.7°C maximum accuracy is maintained across this entire range without calibration, making it suitable for under-hood automotive applications such as engine coolant and transmission fluid sensing where extreme thermal stability is required. The LMT87QDCKTQ1 achieves this using a precision CMOS thermal diode structure with integrated buffering.

Does the LMT87QDCKTQ1 require external calibration to achieve its stated accuracy?

No, the LMT87QDCKTQ1 does not require external calibration to achieve its ±2.7°C maximum accuracy over –50°C to +150°C. This specification is guaranteed by Texas Instruments' production test and characterization process, and the device's transfer function is factory-trimmed. The LMT87QDCKTQ1 uses a parabolic model (–13.6 mV/°C base slope with second-order correction) that is pre-characterized in Table 8-1 of its datasheet, enabling direct lookup or polynomial interpolation in host firmware without per-unit calibration.

Can the LMT87QDCKTQ1 drive an ADC input directly without an external op-amp?

Yes, the LMT87QDCKTQ1 can drive most SAR ADC inputs directly due to its ±50 µA push-pull output stage and low output impedance. Its ability to source/sink up to 50 µA enables rapid charging of typical ADC sampling capacitors (e.g., 10–20 pF). For capacitive loads ≤1100 pF, no series resistor is required. The LMT87QDCKTQ1's 0.7-ms power-on time also aligns well with common ADC sampling sequences, allowing tight synchronization between sensor activation and conversion start.

How does the LMT87QDCKTQ1 handle power supply noise coupling to its output?

The LMT87QDCKTQ1 exhibits supply-noise attenuation of approximately 40 dB above 10 kHz, as shown in Figure 7-8 of its datasheet. While bypass capacitance is optional, TI recommends placing a 0.01 µF ceramic capacitor within 5 cm of the VDD pin in noisy automotive environments. This reduces AC coupling from the supply rail into the output voltage, preserving measurement fidelity-especially critical when the LMT87QDCKTQ1 feeds high-resolution ADCs in infotainment or ADAS modules.

Is the LMT87QDCKTQ1 pin-compatible with legacy LM35 or LM20 temperature sensors?

The LMT87QDCKTQ1 is footprint-compatible-not pin-compatible-with the LM35 and LM20 in SC70-5 packaging. While all three share the same 2.00 mm × 1.25 mm body and 5-pin SOT outline, the LMT87QDCKTQ1 assigns VDD to pins 1, 4, and 5 (three parallel supply connections), GND to pin 2, and OUT to pin 3-unlike the LM35's single VDD (pin 4), GND (pin 2), and OUT (pin 3) configuration. Layout adaptation is required, but PCB real estate and mounting process remain identical.