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The FR6391 is a CMOS IC that has a microphone
peripheral circuit and an echo generation circuit for
karaoke use, on a single chip.
• High-performance digital echo circuit using 44-Kbit
• A mic amplifier with an ALC makes it possible to
handle overload input, and the ALC operating
voltage can be externally set to the desired value.
• Built-in mic volume, echo volume, and feedback
• Internal micmixing amplifier
• The clock has an internal current control-type
oscillation circuit, and the generation of unnecessary
oscillation can be prevented because the clock does
not affect anything external to the unit.
• Internal Auto Reset circuit that functions when the
power supply is turned on.
• MIC Volume, Echo Volume, and Feedback Volume
are controlled by I2C Bus or DC control.
• 5V single power supply
• Wireless Microphone
• Karaoke System
• Consumer Audio Applications
• Car Entertainment System