DirectDriveヘッドフォンアンプ、コモンモードノイズを除去
SUNNYVALE, CA-May 27, 2003-Maxim Integrated Products
(NASDAQ: MXIM) introduces the MAX4409 headphone amplifier. The MAX4409 audio amplifier combines Maxim's patented DirectDrive™ architecture, low 5mA supply current, and a common-mode sense input allowing the amplifier to reject common-mode noise.
DirectDrive produces a ground-referenced audio output signal from a single supply to eliminate additional large DC-blocking capacitors required in conventional headphone amplifier designs. This saves cost, board space, and component height. The common-mode voltage sensing feature minimizes ground-loop noise when the headphone amp is used as a line out connection to other grounded equipment, such as a PC connected to a home HiFi system.
The MAX4409 operates from a single 1.8V to 3.6V supply, delivers up to 80mW per channel into a 16Ω_ load, and has low 0.003% THD + N. A high 86dB power-supply rejection ratio allows operation from noisy digital supplies without additional power conditioning. The MAX4409 includes ±8kV ESD protection on the headphone outputs and comprehensive click-and-pop circuitry to eliminate audible clicks and pops on startup and shutdown. The MAX4409 has short-circuit and thermal-overload protection and a low-power shutdown mode that reduces supply current draw to only 6mA.
Specified over the extended (-40°C to +85°C) temperature range, the MAX4409 is available in 16-pin QFN (4mm x 4mm x 0.8mm) or 14-pin TSSOP packages. Prices start at $0.80 (100k-up, FOB USA). For complete details, see Maxim's Audio website at www.maxim-ic.com/audio.
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