MAXIM Integrated Products has released the MAX9770, an integrated audio amplifier optimised for applications including PDAs, digital cameras, and mobile phones. It is available from Arrow Electronics .
It combines the benefits of Maxim's low EMI, filterless, Class D amplifier technology with a DirectDrive headphone amplifier. This results in a low cost, low component count audio amplifier solution.
The 1.2W, low-EMI, filterless, mono Class D amp offers the audio quality typically associated with linear amps (Class AB) and the benefits of high efficiency (80%) Class D operation. The spread-spectrum modulation scheme reduces EMI emissions up to 6dB more than competing Class D solutions. This allows it to meet FCC EMI levels without additional filtering. Single 2.5V to 5.5V operation with high 85dB PSRR allows the device to operate directly from a lithium-ion (Li+) battery, saving the cost of additional regulation.
The low 0.02% THD+N ensures high quality audio playback. The 80mW DirectDrive headphone amplifier produces a ground referenced output from a single supply. This eliminates the two bulky dc-blocking capacitors typically required between the amplifier and headphone. Click-and-pop suppression eliminates audible transients on power and shutdown cycles.
The MAX9770 includes selectable gain levels and a three way input mixer. It is available in small 28 pin TQFN or TSSOP packages. It includes short-circuit and thermal overload protection and operates over the extended temperature range from -40°C to 85°C.