AKM's AK4730 exceeds Class-AB performance with Class-D efficiency. The input to AK4730 is digital and supports two-channel, 192kHz sampling. The chip combines a two-channel PWM modulator with pre-driver circuitry for external MOSFETs. Unlike other solutions that use two voltage levels for modulation (H-Bridge), AKM's Class D products utilize an advanced multi-reference E-Bridge architecture that achieves higher linearity and SNR performance for audio playback with fidelity closer to the original sound.
With an integrated driver, the AK4730 MOSFET output stage is a simple circuit and is easily incorporated into an audio system. Output power to suit system requirements can be readily achieved by changing the MOSFETs. In addition to an on-chip PWM modulator and MOSFET driver, the AK4730 has built-in individual channel digital volume controls, tone controls, digital-realm output stage power supply regulation and an overload detection circuit. Simply connecting the power MOSFETs permits a complete class-D amplifier configuration. When combined with the AK4113 Digital Audio Interface IC, ultra-low crosstalk six-channel solutions are realized, simplifying the engineering of high-performance multi-channel audio systems.
AK4730 samples in an 80-pin HQFP package as well as 70W and 100W output evaluation boards are available now. The AKM 4730 modulator incorporates True Fidelity E-Bridge technology under license from JAM Technologies, Inc. True Fidelity and E-Bridge are registered trademarks of JAM Technologies, Inc.
(Sarah Rushton-Read)
