NXP Semiconductors LM75BDP/DG,118

Overview

LM75BDP/DG,118 from NXP Semiconductors is a digital temperature sensor and thermal watchdog IC featuring an on-chip bandgap sensor, 11-bit sigma-delta ADC, I²C-bus interface, open-drain OS output, and programmable overtemperature shutdown with hysteresis - used for ambient temperature monitoring and system-level thermal protection in embedded controllers.

For engineers reviewing the LM75BDP/DG,118 datasheet, LM75BDP/DG,118 pinout, LM75BDP/DG,118 application, or LM75BDP/DG,118 equivalent, key selection considerations include its 0.125 °C resolution, −55 °C to +125 °C operating range, 2.8 V–5.5 V supply, TSSOP8 package, and configurable OS comparator/interrupt mode with fault queue.

Technical Context

The LM75BDP/DG,118 implements a sigma-delta A-to-D converter with 100 ms conversion period and 10 ms active conversion time, enabling low-power periodic sensing without bus interference. Its I²C interface supports up to 400 kHz clock rate and includes bus fault timeout (50 ms min) to prevent lockup.

Temperature data is stored in an 11-bit two's complement Temp register (0.125 °C resolution), while Tos and Thyst set-point registers use 9-bit two's complement format (0.5 °C resolution) for overtemperature threshold and hysteresis comparison - with only the 9 MSB of Temp used during comparison logic.

Key Specifications

Pinout & Package

TSSOP8 package (SOT505-1), 3 mm × 3 mm body, 0.65 mm pitch, lead-free, RoHS-compliant.

Key Features

Applications

Equivalent & Alternatives

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

Compared with LM75BDP/DG,118, the LM75BD,118 offers identical performance in a larger SO8 package suited for manual assembly and thermal margin, while the LM75BTP,147 delivers superior thermal performance in a smaller, thermally optimized HWSON8 package - both share full register compatibility and pinout alignment within their respective packages.

Availability

LM75BDP/DG,118 is available at Aetrix Electronics and suitable for industrial controllers, embedded network switches, and medical diagnostic equipment requiring stable component supply across long production lifecycles.

Supply support for LM75BDP/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 leader focused on secure connectivity solutions for automotive, industrial, and IoT applications, with deep expertise in mixed-signal and sensor integration.

The LM75B product line was designed specifically for embedded thermal management - delivering high-resolution, I²C-compatible temperature sensing with autonomous watchdog capability in compact, industry-standard packages.

FAQ

What is the default power-up configuration of the LM75BDP/DG,118?

At power-up, the LM75BDP/DG,118 initializes in normal operation mode with OS comparator mode enabled, OS active low, Tos = 80 °C, Thyst = 75 °C, and fault queue = 1. This allows immediate stand-alone thermostat operation without host initialization. The first temperature reading after power-up is invalid and must be discarded; subsequent reads reflect accurate conversions updated every 100 ms.

How does the LM75BDP/DG,118 handle I²C bus faults?

The LM75BDP/DG,118 incorporates built-in bus fault timeout: if SDA remains low for >50 ms, the device automatically resets its I²C interface to idle state and releases SDA, preventing bus lockup. This feature eliminates the need for external bus recovery circuitry and ensures robust communication in noisy industrial environments where the LM75BDP/DG,118 is commonly deployed.

Can the LM75BDP/DG,118 operate from a 3.3 V supply?

Yes, the LM75BDP/DG,118 operates across 2.8 V to 5.5 V, making it fully compatible with standard 3.3 V logic systems. Its I²C interface functions correctly at 3.3 V with appropriate pull-up resistors (typically 10 kΩ), and all specifications - including accuracy, resolution, and OS timing - are guaranteed across this entire voltage range per the official NXP datasheet Rev. 6.1.

What is the meaning of "TSSOP8" in the LM75BDP/DG,118 package designation?

TSSOP8 refers to the LM75BDP/DG,118's plastic thin shrink small outline package with 8 leads and 3.0 mm body width (SOT505-1). It features gull-wing leads, 0.65 mm pitch, and is RoHS-compliant. This package provides better thermal performance and smaller footprint than SO8, while remaining compatible with standard SMT reflow processes - a key reason for selecting LM75BDP/DG,118 in space-constrained industrial designs.

How does the OS output behave in comparator versus interrupt mode on the LM75BDP/DG,118?

In comparator mode, the LM75BDP/DG,118's OS output asserts when temperature exceeds Tos and de-asserts when it falls below Thyst - behaving like a hardware thermostat. In interrupt mode, OS asserts on Tos crossing and remains asserted until any register is read, enabling host-driven event logging. Both modes support programmable polarity and fault queue, but only interrupt mode requires software interaction to clear the OS flag.