NXP Semiconductors LM75ADP/DG,118

Overview

LM75ADP/DG,118 from NXP Semiconductors is a digital temperature sensor and thermal watchdog IC featuring an on-chip bandgap sensor and 11-bit sigma-delta ADC, delivering 0.125 °C temperature resolution over −55 °C to +125 °C. It provides programmable overtemperature shutdown (Tos = 80 °C default), hysteresis (Thyst = 75 °C default), and open-drain OS output with comparator or interrupt mode-used in PC thermal management, industrial controllers, and embedded system protection.

For engineers reviewing the LM75ADP/DG,118 datasheet, LM75ADP/DG,118 pinout, LM75ADP/DG,118 application, or LM75ADP/DG,118 equivalent, key selection criteria include I²C-bus compatibility (up to 8 devices), TSSOP8 package footprint, ±2 °C accuracy from −25 °C to +100 °C, 3.5 µA shutdown current, and configurable OS fault queue (1–6 consecutive faults).

Technical Context

The LM75ADP/DG,118 implements a sigma-delta A-to-D conversion architecture with internal bandgap reference and oscillator, performing temperature measurements every 100 ms in normal mode. Its 11-bit temperature register stores 2's complement data with 0.125 °C LSB, while Tos and Thyst registers use 9-bit 2's complement format (0.5 °C LSB) for comparison logic.

OS output behavior is determined by configuration bits: B1 selects comparator vs. interrupt mode; B2 sets active-HIGH/LOW polarity; B3–B4 define fault queue depth (1/2/4/6 conversions); and B0 controls normal/shutdown operation. The device powers up with Tos = 80 °C, Thyst = 75 °C, OS comparator mode, active-LOW, and fault queue = 1.

Key Specifications

Pinout & Package

TSSOP8 package (SOT505-1), 3 mm body width, 0.65 mm pitch - surface-mount compatible with standard reflow profiles and space-constrained PCB layouts.

Key Features

Applications

Equivalent & Alternatives

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

Compared with STLM75DT, LM75ADP/DG,118 offers identical functionality and drop-in compatibility; versus MAX31826ATM+, it provides simpler I²C integration and hardware OS signaling but trades off absolute accuracy and non-volatile storage.

Availability

LM75ADP/DG,118 is available at Aetrix Electronics and suitable for server rack thermal monitoring, industrial PLC guarding, and embedded edge gateway thermal management requiring stable component supply across extended product lifecycles.

Supply support for LM75ADP/DG,118 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

NXP Semiconductors is a global semiconductor company headquartered in Eindhoven, Netherlands, specializing in secure connectivity solutions for automotive, industrial, and IoT applications.

The LM75A product line was designed as a precision, low-power digital temperature sensor family targeting thermal management in resource-constrained embedded systems-emphasizing I²C simplicity, hardware-based thermal alerting, and wide industrial temperature range compliance.

FAQ

What is the default power-up configuration of the LM75ADP/DG,118?

At power-up, the LM75ADP/DG,118 initializes in normal operation mode with OS comparator mode enabled, Tos set to 80 °C, Thyst to 75 °C, OS active-LOW, and fault queue = 1. The temperature register begins conversion after ~100 ms and is ready for readout. This allows immediate stand-alone thermostat operation without host initialization-critical for safety-critical thermal guardrails in the LM75ADP/DG,118.

How does the LM75ADP/DG,118 handle I²C bus contention with multiple devices?

The LM75ADP/DG,118 uses three hardware address pins (A2–A0) to generate a unique 7-bit I²C slave address (1001xxx), supporting up to eight devices on the same bus without software arbitration. Each pin must be hard-wired to VCC or GND-floating inputs are prohibited. This deterministic addressing eliminates bus collisions and simplifies multi-sensor thermal mapping in systems using the LM75ADP/DG,118.

Can the LM75ADP/DG,118 operate reliably at 2.8 V supply?

Yes-the LM75ADP/DG,118 is fully specified from 2.8 V to 5.5 V. At 2.8 V, it maintains ±2 °C accuracy (−25 °C to +100 °C), 100 ms conversion time, and functional I²C communication. Supply current remains ≤100 µA in normal mode, making it suitable for low-voltage battery-powered applications where the LM75ADP/DG,118 delivers consistent thermal sensing performance.

What is the maximum sink current capability of the OS output on the LM75ADP/DG,118?

The OS output of the LM75ADP/DG,118 is rated for up to 10 mA sink current per Absolute Maximum Ratings (Table 15). In typical operation with a 10 kΩ pull-up to 3.3 V, it delivers ~0.33 mA-well within safe operating limits. This ensures robust interfacing with microcontroller interrupt inputs, optocouplers, or discrete transistor switches in thermal protection circuits using the LM75ADP/DG,118.

Does the LM75ADP/DG,118 support both comparator and interrupt modes for the OS output?

Yes-the LM75ADP/DG,118 supports two distinct OS output behaviors via Configuration Register bit B1. Comparator mode toggles OS based on Tos/Thyst hysteresis (like a hardware thermostat), while interrupt mode latches OS active until any register is read. Both modes are fully programmable and retain state through shutdown, enabling flexible thermal alert strategies in systems deploying the LM75ADP/DG,118.