LM Comparators Family (16 parts in our catalog)

The LM series of voltage comparators represents an industry-standard family of integrated circuits designed to operate over a wide range of supply voltages. Developed originally by National Semiconductor and now produced by various manufacturers including Texas Instruments, ON Semiconductor, and STMicroelectronics, these devices are essential for comparing two analog signals. They are primarily utilized in applications requiring level detection, zero-crossing sensing, and simple analog-to-digital conversion where low power consumption and robust performance across temperature ranges are critical design requirements.

Key Features

• Wide supply range from 2V to 36V or dual +/-1V to +/-18V supplies
• Low input bias current typically around 25nA to 250nA
• Open-collector outputs for easy interface with TTL, MOS, and CMOS logic
• Low supply current drain independent of the supply voltage magnitude

Sub-families

Typical Use Cases

Embedded engineers frequently specify LM series comparators for threshold detection and signal conditioning tasks. In power management systems, they serve as over-voltage or under-voltage lockout monitors by comparing a scaled rail voltage against a fixed reference. In motor control and industrial automation, these comparators are employed for zero-crossing detection to synchronize switching actions with the AC line frequency. They are also widely used in battery-powered instrumentation for low-battery indicators and square-wave oscillators. Due to their open-collector output architecture, they are particularly effective in wired-OR configurations and level-shifting applications where the comparator must interface directly with microcontrollers operating at different logic levels, such as 3.3V or 5V logic.

Popular Variants

Top variants from across the family, with specs that differentiate them.

Alternatives to Consider