LM2903DR

Overview

The LM2903DR is a dual voltage comparator from Texas Instruments housed in an 8-pin SOIC package. It operates on a single supply voltage ranging from 2V to 30V, with a common-mode input voltage range that includes ground. The device features open-collector outputs compatible with TTL, MOS, and CMOS logic families. Key electrical characteristics include a maximum input offset voltage of 7mV at 5V, a typical response time of 1.3µs, and a quiescent current of 200µA per comparator. It supports an operating temperature range from -40°C to +125°C.

Feature Summary

• Dual independent voltage comparators designed for single-supply operation over a wide voltage range.
• Common-mode input voltage range extends to ground, allowing direct sensing of low-level signals.
• Open-collector output structure provides flexibility for interfacing with various digital logic families.
• Low power consumption with quiescent current independent of the supply voltage level.

Applications

• Vacuum robot control systems
• Single phase UPS monitoring
• Server PSU management
• Cordless power tool protection

Procurement Notes

Verify the specific manufacturer source, as the LM2903DR part number appears associated with multiple vendors including Texas Instruments and Rohm Semiconductor in public databases. Confirm the datasheet version matches the required specifications, particularly regarding the standard versus B-version performance parameters. Ensure the SOIC-8 package dimensions align with the target PCB footprint before finalizing procurement orders.

Selection Notes

Select this component when a dual comparator with ground-referenced inputs is required for single-supply applications. The open-collector output necessitates an external pull-up resistor; ensure the chosen resistor value supports the desired logic levels and switching speed. Consider the 7mV maximum input offset voltage for precision requirements and verify thermal dissipation capabilities within the 8-SOIC package for the intended ambient conditions.

Part Context

The LM2903 belongs to the industry-standard LM2903/LM393 family of dual comparators. The 'D' suffix indicates the SOIC surface-mount package. This device serves as a foundational analog component for signal conditioning and threshold detection in consumer and industrial electronics, often replacing older discrete transistor solutions with a compact integrated circuit approach.

Replacement Considerations

Public confirmed substitute part numbers include LM2903DT (STMicroelectronics) and LM2903VQDR (Texas Instruments). These alternatives offer pin-compatible replacements within the same comparator family, maintaining similar electrical characteristics and packaging options for direct board upgrades.

FAQ

Does the LM2903DR support negative input voltages?

No, the common-mode input voltage range starts at ground (0V). Input voltages should not go more than 0.3V below the negative supply rail to prevent incorrect output states or excessive input current.

What type of output stage does the LM2903DR utilize?

The device utilizes an open-collector output stage. This requires an external pull-up resistor connected to a positive voltage source to establish a high logic state.