L7918CV

Product Overview

Category: Voltage Regulator
Use: To regulate and stabilize the output voltage in electronic circuits
Characteristics:
- Fixed negative voltage regulator
- Output voltage of -18V
- Maximum output current of 1A
Package: TO-220
Essence: Integrated circuit (IC)
Packaging/Quantity: Typically sold in reels or tubes containing multiple units

Specifications

Input Voltage Range: -35V to -20V
Output Voltage: -18V
Output Current: Up to 1A
Dropout Voltage: 2V
Quiescent Current: 5mA
Line Regulation: 0.04%/V
Load Regulation: 0.3%
Operating Temperature Range: -40°C to +125°C

Pin Configuration

The L7918CV voltage regulator has three pins:

INPUT (IN): Connects to the input voltage source
GROUND (GND): Common ground reference
OUTPUT (OUT): Provides the regulated -18V output voltage

Functional Features

Voltage regulation: The L7918CV ensures a stable -18V output regardless of input voltage fluctuations.
Overcurrent protection: The device includes internal current limiting to protect against excessive load currents.
Thermal shutdown: In case of excessive temperature, the regulator shuts down to prevent damage.

Advantages and Disadvantages

Advantages

Easy to use and integrate into electronic circuits
Provides a stable and reliable -18V output voltage
Internal protection features ensure safe operation

Disadvantages

Fixed output voltage may limit flexibility in certain applications
Dropout voltage of 2V may result in higher power dissipation

Working Principles

The L7918CV is a linear voltage regulator that uses a series pass transistor to regulate the output voltage. It compares the reference voltage with a fraction of the output voltage and adjusts the pass transistor accordingly to maintain a stable -18V output.

Application Field Plans

The L7918CV can be used in various electronic applications, including:

Power supplies: Provides a regulated -18V supply for analog circuits, amplifiers, or sensors.
Audio equipment: Used to generate a negative voltage rail for audio amplifiers or mixers.
Industrial control systems: Ensures stable voltage for control circuitry in industrial automation.

Alternative Models

LM7918: Similar fixed -18V voltage regulator from Texas Instruments
MC7918: Negative voltage regulator with similar specifications from ON Semiconductor
UA7918: Fixed -18V regulator from Fairchild Semiconductor

These alternative models offer similar functionality and can be used as substitutes for the L7918CV.

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Seznam 10 běžných otázek a odpovědí souvisejících s aplikací L7918CV v technických řešeních

Sure! Here are 10 common questions and answers related to the application of L7918CV in technical solutions:

Q: What is L7918CV? A: L7918CV is a voltage regulator IC that provides a fixed output voltage of -18V.
Q: What is the maximum input voltage for L7918CV? A: The maximum input voltage for L7918CV is -35V.
Q: Can L7918CV handle high current loads? A: Yes, L7918CV can handle a maximum output current of 1.5A.
Q: How does L7918CV regulate the output voltage? A: L7918CV uses a series pass transistor to maintain a constant -18V output voltage.
Q: Is L7918CV suitable for both AC and DC input voltages? A: Yes, L7918CV can be used with both AC and DC input voltages.
Q: Does L7918CV require any external components for operation? A: Yes, L7918CV requires input and output capacitors for stability and filtering.
Q: Can L7918CV handle short circuit protection? A: Yes, L7918CV has built-in short circuit protection to prevent damage to the IC.
Q: What is the typical dropout voltage of L7918CV? A: The typical dropout voltage of L7918CV is around 2V.
Q: Can L7918CV operate in a wide temperature range? A: Yes, L7918CV can operate in a temperature range of -40°C to +125°C.
Q: What are some common applications of L7918CV? A: L7918CV is commonly used in power supplies, industrial control systems, and automotive electronics where a regulated -18V voltage is required.

Please note that the answers provided here are general and may vary depending on the specific datasheet and manufacturer's recommendations for L7918CV.