NXP Semiconductors SE95D,112

Overview

SE95D,112 from NXP Semiconductors is an ultra-high-accuracy digital temperature sensor and thermal watchdog IC featuring a 13-bit sigma-delta ADC, I²C-bus interface (up to 400 kHz), and open-drain overtemperature shutdown output (OS). It operates from −55 °C to +125 °C with ±1 °C accuracy (−25 °C to +100 °C), 0.03125 °C resolution, and programmable Tos/Thyst set points - used for real-time thermal monitoring in server power supplies and industrial PLCs.

For engineers reviewing the SE95D,112 datasheet, SE95D,112 pinout, SE95D,112 application, or SE95D,112 equivalent, key selection criteria include its pin-compatible LM75A replacement capability, SO8 package compatibility, 2.8 V–5.5 V supply range, OS fault queue configurability (1/2/4/6 consecutive faults), and dual-mode OS operation (comparator vs. interrupt).

Technical Context

The SE95D,112 integrates an on-chip band gap temperature sensor with a sigma-delta analog-to-digital converter delivering 13-bit two's complement output. Its register bank includes Conf (configurable rate, OS mode, polarity, fault queue), Temp (13-bit read-only), Tos/Thyst (9-bit set-point registers), and ID - all accessed via standard I²C protocol with 7-bit slave address determined by A2–A0 pins.

At power-up, it defaults to normal mode, OS comparator mode, Tos = 80 °C, Thyst = 75 °C, OS active LOW, and 10 conversions/s. Conversion rate is selectable among 0.125/1/10/30 Hz via RATEVAL[1:0], directly impacting supply current (7.0 µA shutdown, ~250 µA typical active) and thermal response latency.

Key Specifications

Pinout & Package

SE95D,112 is housed in an 8-pin SO8 package (SOT96-1), 3.9 mm body width, surface-mount, RoHS-compliant.

Key Features

Applications

Equivalent & Alternatives

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

Compared with LM75AIDR, SE95D,112 delivers 16× finer resolution and configurable fault immunity; versus STTS751DT, it offers simpler register mapping and guaranteed pin compatibility with legacy LM75A layouts - making SE95D,112 optimal for accuracy-critical upgrades without PCB revision.

Availability

SE95D,112 is available at Aetrix Electronics and suitable for server thermal management, industrial PLC temperature monitoring, and telecom power supply protection requiring stable component supply, long-term lifecycle support, and RoHS-compliant sourcing.

Supply support for SE95D,112 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 markets, with deep expertise in mixed-signal sensing and embedded processing.

The SE95D,112 belongs to NXP's precision analog sensor family designed specifically for high-reliability thermal monitoring in mission-critical systems where accuracy, configurability, and I²C interoperability are essential.

FAQ

What is the default power-up configuration of the SE95D,112?

At power-up, the SE95D,112 initializes in normal operation mode with OS comparator mode enabled, Tos = 80 °C, Thyst = 75 °C, OS active LOW, fault queue = 1, and conversion rate = 10 conversions/s. This allows immediate stand-alone thermostat functionality without host initialization - a key feature distinguishing SE95D,112 from basic sensors requiring firmware setup.

How does the SE95D,112 achieve ±1 °C accuracy across −25 °C to +100 °C?

The SE95D,112 achieves ±1 °C accuracy through factory-trimmed band gap sensor calibration and sigma-delta ADC linearity correction stored in on-chip OTP memory. This calibration is applied automatically during temperature conversion - no external compensation or host-side correction is needed to meet the spec. The SE95D,112 datasheet guarantees this performance across its full operating voltage (2.8–5.5 V) and temperature range.

Can the SE95D,112 replace the LM75A in existing designs without hardware changes?

Yes, the SE95D,112 is explicitly specified as a pin-for-pin replacement for the LM75A in SO8 packages, sharing identical pinout, power supply range, I²C address structure, and register map layout. Firmware requiring only 9-bit temperature reads or basic Tos/Thyst writes will operate unchanged - making SE95D,112 a seamless accuracy upgrade path for legacy LM75A-based thermal systems.

What is the function of the A2, A1, and A0 pins on the SE95D,112?

The A2, A1, and A0 pins on the SE95D,112 define the three least-significant bits of its 7-bit I²C slave address, enabling up to eight SE95D,112 devices on a single bus. Each pin must be hard-wired to VCC (logic 1) or GND (logic 0); floating connections are prohibited. The MSBs are fixed at 1001, so valid addresses range from 1001000 (0x48) to 1001111 (0x4F).

How does the OS output behave in comparator mode versus interrupt mode on the SE95D,112?

In comparator mode, the SE95D,112 OS output activates when temperature exceeds Tos and deactivates when it falls below Thyst - behaving like a hardware thermostat. In interrupt mode, OS activates on Tos crossing and remains latched until any register is read or shutdown mode is entered, then re-arms only after Thyst is crossed. This dual-mode flexibility makes SE95D,112 suitable for both autonomous safety cutoffs and firmware-managed thermal alerts.