Description

The SSM2517 is a PDM digital input Class-D power amplifierthat offers higher performance than existing DAC plus Class-Dsolutions. The SSM2517 is ideal for power sensitive applications,such as mobile phones and portable media players, where systemnoise can corrupt the small analog signal sent to the amplifier.The SSM2517 combines an audio digital-to-analog converter(DAC), a power amplifier, and a PDM digital interface on a singlechip. The integrated DAC plus analog ?-? modulator architectureenables extremely low real-world power consumption fromdigital audio sources with excellent audio performance. Usingthe SSM2517, audio can be transmitted digitally to the audioamplifier, significantly reducing the effect of noise sources such asGSM interference or other digital signals on the transmitted audio.The SSM2517 is capable of delivering 2.4 W of continuous outputpower with <1% THD + N driving a 4 ? load from a 5.0 V supply.The SSM2517 features a high efficiency, low noise modulationscheme that requires no external LC output filters. The closed-loop,three-level modulator design retains the benefits of an all-digitalamplifier, yet enables very good PSRR and audio performance. Themodulation continues to provide high efficiency even at low outputpower and has an SNR of 96 dB. Spread-spectrum pulse densitymodulation is used to provide lower EMI-radiated emissionscompared with other Class-D architectures.The SSM2517 has a four-state gain and sample frequency selectionpin that can select two different gain settings, optimized for 3.6 Vand 5 V operation. This same pin also controls the internal digitalfiltering and clocking, which can be set for 64 ? fS or 128 ? fS inputsample rates to support both 3 MHz and 6 MHz PDM clock rates.The SSM2517 has a micropower shutdown mode with a typicalshutdown current of 1 ?A for both power supplies. Shutdown isenabled automatically by gating input clock and data signals. Astandby mode can be entered by applying a designated PDM stopcondition sequence. The device also includes pop-and-click suppressioncircuitry. This suppression circuitry minimizes voltageglitches at the output when entering or leaving the low powerstate, reducing audible noises on activation and deactivation.The SSM2517 is specified over the industrial temperature rangeof ?40?C to +85?C. It has built-in thermal shutdown and outputshort-circuit protection. It is available in a 9-ball, 1.5 mm ? 1.5 mmwafer level chip scale package (WLCSP).Applications Mobile handsets

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Part number: EVAL-SSM2517Z

More details from Analog Devices Inc.