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L78L18ACD
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L78L18ACD

Product Overview

  • Category: Voltage Regulator
  • Use: To regulate and stabilize the output voltage in electronic circuits
  • Characteristics: Low dropout voltage, high current capability, thermal overload protection
  • Package: TO-252 (DPAK)
  • Essence: Linear voltage regulator
  • Packaging/Quantity: Available in reels of 2,500 units

Specifications

  • Input Voltage Range: 7V to 35V
  • Output Voltage: 18V
  • Output Current: Up to 100mA
  • Dropout Voltage: 1.7V (typical)
  • Quiescent Current: 5mA (typical)
  • Operating Temperature Range: -40°C to +125°C

Detailed Pin Configuration

The L78L18ACD voltage regulator has three pins:

  1. Input (VIN): Connects to the input voltage source.
  2. Ground (GND): Connected to the ground reference.
  3. Output (VOUT): Provides the regulated output voltage.

Functional Features

  • Voltage Regulation: The L78L18ACD maintains a constant output voltage of 18V, regardless of changes in the input voltage or load conditions.
  • Low Dropout Voltage: With a dropout voltage of only 1.7V, this regulator can operate efficiently even when the input voltage is close to the desired output voltage.
  • High Current Capability: Capable of delivering up to 100mA of continuous output current.
  • Thermal Overload Protection: Built-in protection mechanism that prevents the regulator from overheating under excessive load or high ambient temperature conditions.

Advantages and Disadvantages

Advantages: - Simple and easy to use. - Provides stable and regulated output voltage. - Suitable for low-power applications. - Offers thermal overload protection.

Disadvantages: - Limited output current capability. - Requires an input voltage higher than the desired output voltage.

Working Principles

The L78L18ACD is a linear voltage regulator that uses a pass transistor to regulate the output voltage. It compares the output voltage with a reference voltage and adjusts the pass transistor accordingly to maintain a constant output voltage. When the input voltage exceeds the desired output voltage, the excess voltage is dissipated as heat.

Detailed Application Field Plans

The L78L18ACD voltage regulator finds applications in various electronic circuits, including:

  1. Power supplies for microcontrollers and other low-power digital devices.
  2. Battery-powered systems requiring a stable voltage source.
  3. Automotive electronics, such as dashboard displays and audio systems.
  4. Industrial control systems and instrumentation.
  5. Consumer electronics, such as portable audio players and small appliances.

Detailed and Complete Alternative Models

  1. LM7805: A popular 5V linear voltage regulator with similar characteristics but a different output voltage.
  2. LT1084: A high-current adjustable linear voltage regulator suitable for demanding applications.
  3. LM317: An adjustable linear voltage regulator capable of providing a wide range of output voltages.

These alternative models offer different output voltages, current capabilities, and package options, allowing users to choose the most suitable option for their specific requirements.

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技術ソリューションにおける L78L18ACD の適用に関連する 10 件の一般的な質問と回答をリストします。

Sure! Here are 10 common questions and answers related to the application of L78L18ACD in technical solutions:

  1. Q: What is L78L18ACD? A: L78L18ACD is a voltage regulator IC that provides a fixed output voltage of 18V.

  2. Q: What is the input voltage range for L78L18ACD? A: The input voltage range for L78L18ACD is typically between 20V and 35V.

  3. Q: What is the maximum output current of L78L18ACD? A: The maximum output current of L78L18ACD is 100mA.

  4. Q: Can L78L18ACD handle higher input voltages than its output voltage? A: No, L78L18ACD is designed to regulate the output voltage to a fixed value and cannot handle higher input voltages.

  5. Q: Is L78L18ACD suitable for battery-powered applications? A: Yes, L78L18ACD can be used in battery-powered applications as long as the input voltage is within its specified range.

  6. Q: Does L78L18ACD require any external components for operation? A: Yes, L78L18ACD requires input and output capacitors for stability and filtering purposes.

  7. Q: Can L78L18ACD tolerate short circuits or overloads? A: No, L78L18ACD does not have built-in protection against short circuits or overloads. External protection circuitry may be required.

  8. Q: Can L78L18ACD operate in high-temperature environments? A: L78L18ACD has a maximum operating temperature of 125°C, so it can operate in moderately high-temperature environments.

  9. Q: Can L78L18ACD be used to power sensitive analog circuits? A: Yes, L78L18ACD is suitable for powering sensitive analog circuits as it provides a stable and regulated output voltage.

  10. Q: Are there any alternatives to L78L18ACD for regulating 18V? A: Yes, there are other voltage regulator ICs available in the market that can regulate an output voltage of 18V. Some alternatives include LM7818 and LT1086-18.