LM4879MMX/NOPB vs LM4991MAX/NOPB
| Part Number |
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| Category | Linear - Amplifiers - Audio | Linear - Amplifiers - Audio |
| Manufacturer | Texas Instruments | Texas Instruments |
| Description | IC AMP CLSS AB MONO 1.1W 10VSSOP | IC AMP CLASS AB MONO 1.5W 8SOIC |
| Package | -Reel® | Bulk |
| Series | Boomer® | Boomer® |
| Type | Class AB | Class AB |
| Features | Depop, Shutdown, Thermal Protection | Depop, Shutdown, Thermal Protection |
| Voltage - Supply | 2.2V ~ 5.5V | 2.2V ~ 5.5V |
| Operating Temperature | -40°C ~ 85°C (TA) | -40°C ~ 85°C (TA) |
| Mounting Type | Surface Mount | Surface Mount |
| Package / Case | 10-TFSOP, 10-MSOP (0.118\", 3.00mm Width) | 8-SOIC (0.154\", 3.90mm Width) |
| Supplier Device Package | 10-VSSOP | 8-SOIC |
| Output Type | 1-Channel (Mono) | 1-Channel (Mono) |
| Max Output Power x Channels @ Load | 1.1W x 1 @ 8Ohm | 1.5W x 1 @ 8Ohm |
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1. What is the Total Harmonic Distortion (THD) of an audio amplifier?
Total Harmonic Distortion (THD) is the distortion component introduced by an audio amplifier during the signal amplification process. the lower the THD, the closer the amplified audio signal will be to the original signal, and usually high quality audio amplifiers have a THD value of less than 1%.
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2. What is a Class D audio amplifier and what are its advantages?
Class D audio amplifiers work through Pulse Width Modulation (PWM) technology and have extremely high efficiency (typically up to 90% or higher), making them suitable for use in portable audio equipment or high-efficiency sound systems. It generates less heat because it reduces energy consumption.
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3. Does the audio amplifier need to match the impedance of the speakers?
Yes, the output impedance of the audio amplifier should match the impedance of the speaker. Typically speakers have an impedance of 4Ω, 8Ω or 16Ω. Matching the impedance ensures that the amplifier delivers maximum power and the best sound quality from the speaker.
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4. How can I improve the thermal performance of my audio amplifier?
Audio amplifiers generate heat when they operate, especially Class A and Class AB amplifiers. Ways to improve heat dissipation include using a larger heat sink, adding a fan, or using a more efficient Class D amplifier. A good thermal design will improve the performance and life of the amplifier.
