EMJ MIJ-NLTP High-Precision CMOS-Based Temperature Sensor

Overview

The EMJ MIJ-NLTP is a high-precision, integrated-circuit temperature sensor engineered for laboratory-grade thermal metrology in demanding environmental and geophysical applications. Unlike traditional Pt100 resistance thermometers requiring external bridge circuitry or specialized data loggers, the MIJ-NLTP embeds a calibrated CMOS analog front-end with intrinsic Pt100 AA-class compliance (per JIS C 1604:2013 and equivalent to IEC 60751:2022 Class AA). It directly converts temperature into a linear millivolt output signal—eliminating calibration drift from lead-wire resistance, excitation current instability, or amplifier gain error. Its operational principle leverages monolithic silicon integration to replicate the standardized Pt100 resistance–temperature relationship with on-chip compensation for nonlinearity, self-heating, and thermal lag. Designed for continuous deployment in atmospheric, pedological, and indoor/outdoor ambient monitoring, it operates reliably across –60 °C to +110 °C with minimal thermal mass and sub-millisecond power-on stabilization.

Key Features

• CMOS-integrated Pt100 AA-class accuracy: ±0.05 °C typical (20–40 °C), ±0.12 °C full range (–60 to +100 °C)
• Ultra-low self-heating error: +0.0012 °C in still air (measured at 13.8 µA total supply current)
• Rapid thermal response: τ_63.2% = 2.6 s in static water; 85.1 s in still air
• Instant electrical stabilization: <600 µs power-on-to-stable-output latency
• High sensitivity: –0.1939 °C/mV output slope, enabling direct voltage-to-temperature conversion without lookup tables
• Low-power architecture: 34.5 µW total dissipation (1.8 µA for bias circuit + 12 µA for sensing element)
• Robust mechanical design: 8 mm OD POM housing; 3 mm SUS304 sensing tip; 80 mm total length (40 mm active zone)
• Flexible power interface: 2.0–30 VDC supply range; three-wire configuration (Red = V_IN, White = V_OUT, Black = GND)

Sample Compatibility & Compliance

The MIJ-NLTP is validated for contact-based temperature measurement in heterogeneous media including ambient air, saturated soil columns, aqueous solutions, and sealed enclosures. Its stainless-steel sensing tip (SUS304) ensures chemical inertness in mildly acidic or alkaline environments and mechanical durability during insertion into compacted soils or granular substrates. The device conforms to JIS C 1604:2013 (Pt100 AA tolerance), aligning with ISO/IEC 17025-accredited calibration protocols for environmental monitoring networks. While not certified for medical or explosive atmospheres, its performance meets requirements for GLP-compliant field studies, ASTM D5372 (soil temperature profiling), and WMO Guide to Meteorological Instruments and Methods of Observation (CIMO Guide) Annex 4.1 for automatic weather stations.

Software & Data Management

As an analog voltage-output sensor, the MIJ-NLTP interfaces natively with any DAQ system supporting mV-range differential inputs (e.g., National Instruments USB-6211, Keysight 34972A, Campbell Scientific CR1000X). Its linear output eliminates need for polynomial fitting—temperature (°C) = (V_OUT − 219.55 mV) / (–0.1939 mV/°C). When integrated into regulated data acquisition workflows, it supports audit-trail-capable logging per FDA 21 CFR Part 11 when paired with compliant software (e.g., LabVIEW with digital signature modules or MATLAB Production Server with traceable timestamping). Calibration certificates (NIST-traceable) are available upon request and include uncertainty budgets per GUM (JCGM 100:2008).

Applications

• Long-term microclimate monitoring in ecological research stations and smart agriculture systems
• Soil thermal conductivity and heat flux modeling in hydrological and permafrost studies
• Validation of infrared thermography and thermal imaging systems in controlled chambers
• Reference-grade temperature input for HVAC commissioning and building energy audits
• Calibration transfer standards in metrology labs maintaining secondary temperature references
• Embedded thermal feedback in precision incubators, environmental test chambers, and bioreactors

FAQ

Does the MIJ-NLTP require external signal conditioning or bridge circuitry?
No. It outputs a ratiometric voltage proportional to temperature and operates independently of external resistors or amplifiers.
Is the sensor suitable for immersion in groundwater or seawater?
The SUS304 tip provides corrosion resistance in freshwater; prolonged exposure to saline or brackish water requires optional epoxy potting or Teflon sheathing.
Can multiple MIJ-NLTP sensors share a common power rail?
Yes—each draws only 13.8 µA, enabling daisy-chained configurations up to 70+ units on a single 30 V supply without significant voltage drop.
What is the recommended sampling interval for achieving stated accuracy?
For ±0.05 °C repeatability, sample at ≥1 Hz; lower rates (<0.1 Hz) reduce thermal noise but do not improve static accuracy.
Is NIST-traceable calibration documentation included by default?
No—certificates are provided as an optional add-on service with documented uncertainty budgets and ISO/IEC 17025 accreditation.