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LM311P

TILM311P

Texas Instruments
Comparator Standard (General Purpose) DTL, MOS, Open-Collector, Open-Emitter, RTL, TTL 8-PDIP
Active21,110 in stock
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Overview

The LM311P is a high-speed voltage comparator designed to operate over a wide range of supply voltages from standard 15V op-amp rails down to a single 5V logic supply. It features a flexible output stage that is compatible with RTL, DTL, and TTL logic, and can drive lamps or relays with up to 50mA of current.

Why Choose This Part

The LM311P offers a fast response time of 165ns and includes a unique strobe capability for logic-controlled operation. Its open-collector and open-emitter output configuration allows for easy wire-ORing and simplifies level shifting between different logic families.

Applications

Zero-Crossing Detectors
Converting sine waves to square waves for timing and frequency measurement in power systems.
Window Comparators
Monitoring a voltage signal to ensure it stays within a predefined upper and lower threshold.
Peak Detectors
Identifying the maximum voltage level of an analog signal for signal processing applications.
Oscillators
Serving as the core switching element in relaxation oscillators and square-wave generators.

Key Specifications

Type Standard (General Purpose)
Output Type DTL, MOS, Open-Collector, Open-Emitter, RTL, TTL
Mounting Type Through Hole
Package / Case 8-DIP (0.300", 7.62mm)
Number of Elements 1
Operating Temperature 0degC ~ 70degC
Current - Output (Typ) 50mA
Supplier Device Package 8-PDIP
Current - Quiescent (Max) 7.5mA
Current - Input Bias (Max) 0.25uA @ +/-15V
Voltage - Input Offset (Max) 7.5mV @ +/-15V
Voltage - Supply, Single/Dual (+/-) 3.5V ~ 30V, +/-1.75V ~ 15V

Getting Started

For prototyping, the 8-PDIP package is breadboard-compatible and requires only a pull-up resistor on the output pin to interface with 5V or 3.3V microcontrollers. Engineers should ensure bypass capacitors are placed close to the power pins to maintain stability during fast output transitions.

Also Consider

LM393N TITexas Instruments - A lower-power dual comparator in a PDIP package for applications that do not require the LM311's high output current or strobe features.
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