- Mono class D work
- No output filter required for inductive loads
- Externally set gain
- Very fast start-on time: 17 μs (typical)
- Minimal external components
- "Click" sound suppression circuit
- Micropower shutdown mode
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Space-saving 0.4mm pitch micro SMD and LLP TM pack
illustrate
The LM4673 is a single-supply, high-efficiency, 2.65W, mono, Class-D audio amplifier. Low-noise, filter-free PWM architecture eliminates the need for output filters, reducing the number of external components, board area consumption, system cost, and simplifying design.
The LM4673 is designed to meet the needs of mobile phones and other portable communication devices. Operating on a 5V single supply supply, it is capable of driving less than 1% THD + N4Ω speaker load at 2.1W continuous average output Its flexible power requirements allow operation from 2.4V to 5.5V.
A typical Class AB amplifier is more efficient than the LM4673 with speaker loads. With a 3.6V supply driving an 8Ω speaker, the IC has an efficiency of 80% at 100mW and 88% of the output power at 400mW.
The LM4673 has a low-power downtime mode. Shutdown can enable the drive shutdown pin to Logical Low (GND).
The LM4673's gain is an external configuration that allows independent gain control by summarizing signals from multiple sources. Output short-circuit protection and thermal overload protection prevent damage to equipment under fault conditions.
Key specifications:
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■ 3.6V, 400mW efficiency is 8Ω speakers
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88% (typical)
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■ At 3.6V efficiency, 100MW to 8Ω speakers
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80% (typical)
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■ 5V with an efficiency of 8W for 1Ω speakers
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86% (typical)
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■ Quiescent current, 3.6V power supply
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2.1 mA (typical)
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■ Total shutdown power current
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0.01μA (typical)
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■ Single supply voltage range
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2.4V to 5.5V
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■ PSRR, F = 217Hz
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78 dB
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apply
- mobile phone
- handheld computer
- Portable electronic devices
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