Introduction
You may already be aware that amplifiers are often used to amplify the input voltage or power. Voltage amplifiers modify and increase only the input voltage, whereas power amplifiers increase all power, including voltage and current. Thus this article is about power amplifiers. Here in this Tutorial, we will see “LM380 Audio Power Amplifier”.
Brief Overview of LM380
The LM380 is a powerful audio amplifier designed for consumer use. Gain is internally regulated at 34 dB to keep system expenses to a minimum. Inputs can be ground referenced thanks to a special input stage. The output self-centers automatically to one-half the source voltage.
Internal heat limiting and short circuit protection are present in the output. It uses a copper lead frame with a heat sink made up of the middle three pins on either side. As a result, using the IC becomes simple.
Features of LM380 Amplifier IC
- Wide supply voltage range: 10V-22V
- Low quiescent power drain: 0.13W (V S = 18V)
- Voltage gain fixed at 50
- High peak current capability: 1.3A
- Input referenced to GND
- High input impedance: 150k?
- Low distortion
- The quiescent output voltage is at one-half of the supply
voltage Standard dual-in-line package
Pinouts
| Pin Number | Pin Name | Description |
| 1 | Bypass | A bypass pin to connect a decoupling capacitor |
| 2 | IN+ | The Non-Inverting pin to receive an audio signal |
| 3, 4, 5, 7, 10, 11, 12 | GND | Ground Pins |
| 6 | IN- | The Inverting Pin of an amplifier is normally grounded |
| 8 | VOUT | The output pin of the amplifier |
| 14 | VCC | Connected to power supply |
| 9, 13 | NC | Not Connected |
(1) 6W Bridge Power Amplifier
(2) A Mini Audio Amplifier
(3) Megaphone Circuit using LM380
Application Uses
- Radio Receivers
- Televisions
- Power Converters
- Stereo amplifiers, etc
