LP311PSR

Overview

The LP311PSR is a low-power differential comparator manufactured by Texas Instruments, housed in an 8-pin SOP package. It operates from supply voltages ranging from ±15 V down to a single 3-V source. The device features a typical response time of 1.2 μs and offers an output drive capability of 25 mA. Electrical characteristics include a maximum input offset voltage of 7.5 mV at 25°C and a typical bias current of 15 nA. It supports offset balancing and strobe functionality for precise control.

Feature Summary

• Low power consumption with typical drain of 900 μW at 5-V supply
• Strobe capability allows turning off the output regardless of input states
• Offset balancing feature minimizes input offset voltage
• Compatible with RTL-DTL, TTL, and MOS logic circuits

Applications

• Battery-powered applications requiring low current drain
• Threshold detection circuits where fast response is not critical
• Logic interface circuits between analog sensors and digital systems
• Window comparator designs utilizing strobe functionality

Procurement Notes

Verify that the specific orderable part number matches the required SOP-8 package configuration. Confirm the operating temperature range aligns with system requirements, as the LP311 variant is rated for 0°C to 70°C. Ensure compatibility with existing PCB footprints designed for standard LM311 pinouts due to identical pin assignments. Check for RoHS compliance status if environmental regulations apply to the final assembly.

Selection Notes

Select this component when power efficiency is prioritized over high-speed switching capabilities. The LP311 series provides a 30:1 reduction in power consumption compared to the LM311 series, albeit with a slower response time. It is suitable for general-purpose comparison tasks where input currents must be minimized. Consider the LP211 variant if operation in colder environments below 0°C is necessary.

Part Context

The LP311PSR belongs to the LPx11 family of low-power differential comparators from Texas Instruments. These devices are designed as low-power alternatives to the industry-standard LM211 and LM311 comparators. They utilize stable, high-value ion-implanted resistors to achieve significant power savings while maintaining functional compatibility with standard logic families.

Replacement Considerations

The LP311PSR shares the same pinout as the LM311PSR and LM311DR, allowing for potential direct replacements in designs where speed is not the primary constraint. Verify that the application can tolerate the 1.2 μs response time characteristic of the LP311 series.