Texas Instruments LM35H

Overview

LM35H from Texas Instruments is a precision centigrade temperature sensor IC with analog voltage output directly proportional to ambient temperature, featuring ±0.4°C accuracy at 25°C, −55°C to +150°C operating range, and 10 mV/°C linear scale factor. It operates from 4 V to 30 V supply, draws less than 60 µA quiescent current, and delivers low-impedance output (0.1 Ω) for direct interfacing with ADCs or instrumentation amplifiers in thermal monitoring circuits.

For engineers reviewing the LM35H datasheet, LM35H pinout, LM35H application, or LM35H equivalent, this page provides verified technical context, package-specific pin functions, real-world application mappings, and validated alternative parts - all grounded in TI's SNIS159H production datasheet and official orderable information.

Technical Context

The LM35H implements a delta-V_BE temperature-sensing element buffered by a Class-A amplifier, producing a ratiometric analog output without requiring external calibration. Its transfer function is strictly defined as V_OUT = 10 mV/°C × T, where T is case temperature in °C.

It operates in a single functional mode: continuous analog voltage output sourcing only (sinking capability limited to 1 µA), with no digital interface, configuration registers, or power-down states. Output impedance remains ≤0.1 Ω under 1-mA load, enabling stable operation into high-impedance readout circuitry without buffering.

Key Specifications

Pinout & Package

LM35H is supplied in the hermetic TO-CAN (NDV) package, 3-pin metal can with case connected to GND. Dimensions: 4.699 mm × 4.699 mm. Designed for high-reliability, high-temperature environments including aerospace and industrial control.

Key Features

Applications

Equivalent & Alternatives

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

Compared with LM35H, LM35C trades hermetic packaging and extended temperature range for lower cost and plastic handling, while ADT7320 replaces analog simplicity with digital precision and interface complexity - making LM35H optimal for rugged, analog-centric thermal monitoring where minimal component count and proven reliability are critical.

Availability

LM35H is available at Aetrix Electronics and suitable for power supply thermal monitoring, battery pack sensing, HVAC ambient measurement, and industrial motor protection requiring stable component supply across extended temperature ranges and long product lifecycles.

Supply support for LM35H 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 leader specializing in analog, embedded processing, and connectivity technologies, with decades of heritage in precision analog IC design and high-reliability manufacturing.

The LM35H belongs to TI's precision analog temperature sensor product line, engineered specifically for applications demanding centigrade-linear output, wide operating range, and hermetic reliability in harsh thermal environments.

FAQ

What is the maximum operating temperature of the LM35H?

The LM35H is rated for continuous operation from −55°C to +150°C. This full-range specification is validated per TI's SNIS159H datasheet and applies to the hermetic TO-CAN (NDV) package. At 150°C, output remains linear with ±0.8°C accuracy, making LM35H suitable for under-hood automotive and industrial power electronics thermal monitoring where other plastic-packaged variants fail.

Does the LM35H require external calibration or trimming?

No, the LM35H does not require external calibration or trimming. It achieves ±0.4°C accuracy at 25°C and ±0.8°C over its full −55°C to +150°C range through wafer-level laser trimming and inherent process matching. TI's production test flow ensures these specifications without user intervention - enabling drop-in deployment in production systems.

Can the LM35H drive an ADC input directly?

Yes, the LM35H can drive most 12-bit and higher-resolution SAR ADC inputs directly. Its 0.1 Ω output impedance at 1 mA load and low noise profile ensure minimal loading error and stable settling. For best results, use a 0.1 µF ceramic bypass capacitor between +VS and GND, and keep trace lengths short to avoid EMI coupling - as confirmed in TI's Layout Guidelines section.

What is the supply current consumption of the LM35H at 25°C?

The LM35H draws 56 µA typical quiescent current at 25°C and 5 V supply, rising to 105 µA at −40°C and 158 µA at +125°C. This ultra-low current enables multi-year operation from coin cells in remote sensors and contributes to sub-0.1°C self-heating - a key design value documented in TI's Thermal Characteristics table and Figure 6 of SNIS159H.

Is the LM35H pin-compatible with other LM35 variants like LM35D or LM35C?

No - the LM35H (TO-CAN) has a different pinout and package than LM35D (SOIC-8) or LM35C (TO-92). While all share identical electrical functionality, mechanical compatibility is not guaranteed: LM35H uses Pin 1 (+VS), Pin 2 (VOUT), Pin 3 (GND) in top-view TO-CAN; LM35C uses same pin numbering but in plastic TO-92; LM35D has 8 pins with four N.C. terminals. PCB layout must be redesigned for each variant.