Texas Instruments LM26CIM5-SHA/NOPB

Overview

LM26CIM5-SHA/NOPB from Texas Instruments is a factory-preset, ±3°C accurate overtemperature shutdown thermostat in SOT-23-5 package with 75°C trip point, active-low open-drain OS output, and programmable 2°C/10°C hysteresis via HYST pin. It integrates temperature sensor, reference, DAC, and comparator for thermal protection in microprocessor power rails and fan control circuits.

For engineers reviewing the LM26CIM5-SHA/NOPB datasheet, LM26CIM5-SHA/NOPB pinout, LM26CIM5-SHA/NOPB application, or LM26CIM5-SHA/NOPB equivalent, key selection criteria include trip accuracy (±3°C), VTEMP analog output slope (−10.82 mV/°C), supply current (16 µA typ), hysteresis configuration (GND = 10°C, V+ = 2°C), and open-drain output compatibility with 3.3 V/5 V logic systems.

Technical Context

The LM26CIM5-SHA/NOPB implements a precision analog temperature sensing path feeding an internal comparator with factory-trimmed reference and DAC. Its trip point is fixed at 75°C during manufacturing and cannot be adjusted externally. The comparator's hysteresis is digitally selected by HYST pin voltage level-GND sets 10°C, V+ sets 2°C-enabling noise-immune switching in thermally noisy environments.

VTEMP provides a calibrated analog voltage output following VO = (−3.479 × 10⁻⁶ × (T − 30)²) + (−1.082 × 10⁻² × (T − 30)) + 1.8015 V, enabling post-assembly functional verification and system-level temperature monitoring without external sensors. Output drive capability is limited to ≤1 µA source / ≤40 µA sink to preserve accuracy.

Key Specifications

Pinout & Package

SOT-23-5 (DBV) package: 2.90 mm × 1.60 mm body, 0.95 mm max height, gull-wing leads, RoHS-compliant, lead-free (NOPB).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar thermostat applications.

Compared with LM26CIM5-SHA/NOPB, LM26CIM5-SPA/NOPB offers tighter thermal response at 70°C for space-constrained designs, while LM26CIM5-RPA/NOPB provides greater derating headroom at 65°C-both retain identical interface behavior and calibration traceability.

Availability

LM26CIM5-SHA/NOPB is available at Aetrix Electronics and suitable for microprocessor thermal management, fan control, and portable battery-powered systems requiring stable component supply, long-term lifecycle support, and RoHS-compliant sourcing.

Supply support for LM26CIM5-SHA/NOPB 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 company headquartered in Dallas, Texas, delivering analog and embedded processing solutions for industrial, automotive, and personal electronics markets.

The LM26 product line delivers factory-programmable thermostats targeting thermal protection in space-constrained, low-power systems-designed to replace electromechanical switches and simplify thermal management in high-volume electronics.

FAQ

What is the exact trip temperature of LM26CIM5-SHA/NOPB and how is it set?

The LM26CIM5-SHA/NOPB has a fixed trip temperature of 75°C, programmed during wafer fabrication using laser trimming of internal DAC and reference circuitry. This value is non-adjustable in-circuit and guaranteed over −55°C to +110°C ambient range with ±3°C accuracy. No external components or configuration pins alter this setting-trip point is immutable after manufacture.

How does the HYST pin affect hysteresis behavior in LM26CIM5-SHA/NOPB?

The HYST pin on LM26CIM5-SHA/NOPB selects between two hysteresis values: connecting HYST to GND configures 10°C hysteresis (TOS − THYST = 65°C), while connecting HYST to V+ configures 2°C hysteresis (TOS − THYST = 73°C). This digital control prevents output chatter near the trip point and is implemented via internal comparator threshold shifting-no external resistors or timing components are needed.

Can LM26CIM5-SHA/NOPB be used for undertemperature detection?

No, LM26CIM5-SHA/NOPB is factory-configured exclusively for overtemperature shutdown (OS) with active-low open-drain output. It does not support undertemperature (US) functionality. For undertemperature detection, select alternate variants like LM26CIM5-HHD/NOPB (0°C US) or LM26CIM5-BPB/NOPB (−45°C US), which have different output logic and trip point programming.

What is the purpose and design limitation of the VTEMP pin on LM26CIM5-SHA/NOPB?

The VTEMP pin on LM26CIM5-SHA/NOPB outputs a temperature-proportional analog voltage (1.8015 V at 30°C, −10.82 mV/°C slope) for system-level temperature monitoring and post-assembly testing. Its design limitation is extremely weak drive strength: maximum 1 µA source / 40 µA sink. Connecting low-impedance loads causes voltage droop and measurement error-always interface with high-Z inputs (e.g., 1 MΩ+ ADC) or op-amp buffers.

Is LM26CIM5-SHA/NOPB compatible with 3.3 V microcontroller GPIOs?

Yes, LM26CIM5-SHA/NOPB is fully compatible with 3.3 V microcontrollers. Its open-drain OS output operates from 2.7 V to 5.5 V supply and sinks current when active; a 3.3 V pullup resistor (e.g., 10 kΩ) ensures logic-low voltage ≤0.4 V and logic-high voltage ≈3.3 V. The HYST pin accepts 0.2×V+ to 0.8×V+ thresholds, so at 3.3 V supply, GND (0 V) and 3.3 V are valid hysteresis selections.