LM4990MM/NOPB vs LM4992SD/NOPB
| Part Number |
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| Category | Linear - Amplifiers - Audio | Linear - Amplifiers - Audio |
| Manufacturer | Texas Instruments | National Semiconductor |
| Description | IC AMP CLASS AB MONO 2W 8VSSOP | LM4992 420MW STEREO CELL PHONE A |
| Package | Tape & Reel (TR) | Bulk |
| Series | Boomer® | Boomer® |
| Type | Class AB | Class AB |
| Features | Depop, Shutdown | 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 | 8-TSSOP, 8-MSOP (0.118\", 3.00mm Width) | 14-WFDFN Exposed Pad |
| Supplier Device Package | 8-VSSOP | 14-WSON (4x3) |
| Output Type | 1-Channel (Mono) | 2-Channel (Stereo) |
| Max Output Power x Channels @ Load | 2W x 1 @ 4Ohm | 1.07W x 2 @ 8Ohm |
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1. How to choose a suitable audio amplifier?
When choosing an audio amplifier, factors such as output power, total harmonic distortion (THD), signal-to-noise ratio (SNR), efficiency, impedance matching (speaker impedance), and power consumption should be taken into consideration to ensure that it is well-matched with the speakers and audio source equipment.
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2. 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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3. 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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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.
