- 3W output to 8Ω at 5V with THD+N=1%
- Optional spread spectrum mode reduces EMI
- 80% efficiency
- Independent voltage regulator and amplifier shutdown control
- Dynamically selectable regulator output voltage
- Unfiltered Class D
- 3.0V - 5.5V operation
- Low shutdown current
- Click suppression
illustrate
LM48511 integrates a high-efficiency Class-D audio power amplifier boost converter to provide 3W of continuous power to an 8Ω speaker when operating from a 5V supply. When operating from a 4V 3V supply, the LM48511 can be configured to drive an 8Ω load with less than 1% distortion (THD+N) from 1 to 2.5W. Class-D amplifiers feature a low-noise PWM architecture that eliminates output filters, reduces the number of external components, consumes board area, system cost, and simplifies design. An optional spread spectrum modulation technique suppresses RF radiation, further reducing the need for output filters.
The LM48511 switching regulator is a fixed frequency converter that boosts the current mode at 1MHz. Two optional feedback networks enable LM48511 switching regulator, dynamic two different output voltages, to improve efficiency by optimizing the amplifier's supply voltage, battery voltage, and output power requirements.
LM48511 is designed for use with portable devices such as GPS, mobile phones, and MP3 players. High efficiency at 5V 80%, extended battery life compared to boost Class AB amplifiers. Independent regulators and amplifier shutdown control regulators do not require optimized energy savings when high output power is disabled.
This LM48511 gain is set by an external resistor, allowing independent gain control from multiple sources through summarized signals. Output short-circuit protection and thermal overload protection prevent damage to equipment under fault conditions. Superior click and pop suppression eliminates power-up and shutdown sound transients.
Key specifications:
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■ Quiescent supply current
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V DD = 3V V DD = 5V
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9 mAh (typical) 13.5 mAh (typical)
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■ P O is in V DD = 5V, PV1 = 7.8V R L =8Ω，THD + N = 1％
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3.0W (typical)
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■ P O is in V DD = 3 V, PV1 = 4.8 V R L =8Ω，THD + N = 1％
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1W (typical)
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■ P O is in V DD = 5V, PV1 = 7.8V R L =4Ω，THD + N = 1％
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5.4W (typical)
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■ The shutdown current is at V DD = 3V
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0.01μA (typical)
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apply
- GPS
- Portable media
- camera
- mobile phone
- handheld game consoles
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