Wolfson Microelectronics has today announced the latest addition to its AudioPlus Smart Power product line. The WM8400 combines a multimedia CODEC with integrated power management features to deliver the high performance audio and mixing capability, longer battery life and reduced system cost required in the leading multimedia mobile handsets. Wolfson will be demonstrating the WM8400 on its stand at Mobile World Congress in Barcelona from 11-14 February 2008.
WM8400 functions include a high performance multimedia CODEC, on-chip FLL, two DC-DC converters and four LDO regulators, all inside a compact 6x6mm BGA package. Flexible hardware control enables the WM8400 to support the generic power management needs of leading multimedia companion processors. Compared to using separate CODEC and power management chips, which typically require two or more discrete components, the WM8400 can help mobile handset designers to save up to 25 percent on the device bill of materials (BOM) and up to 40 percent on the board footprint.
The WM8400 incorporates a low power audio CODEC, which delivers 98dB SNR performance and supports the signal switching, audio conversion and voice mixing requirements of next-generation mobile phones. This enables designers to quickly add new features and enable flexible end-user modes such as the ability to watch mobile TV while receiving a voice call. The digital core consumes less power than similar devices and can be as low as 5mW during a voice call.
In addition, the WM8400's CODEC is able to select, in software, Class AB or Class D speaker driver operation meaning handset designers can deploy filterless Class D technology into a wider range of increasingly diverse, handheld form factors, where restrictions such as noise and interference previously demanded a Class AB driver topology. System designers may select the most appropriate mode of operation for the anticipated usage scenario, allowing battery life for the end user to be maximised.
The WM8400 also includes a powerful 1W mono speaker driver and low leakage, high PSRR and pop/click suppression enable direct battery connection for the speaker supply. Four headphone driver outputs support conventional, fully differential or cap-less drive. Multiple microphone or analogue line inputs (mono or stereo, single-ended or differential) can be supported and a programmable high-pass filter is provided to remove low frequency noise from the input signal.
The digital audio interface supports most commonly-used data formats and clocking schemes while time-division multiplexing and an additional DAC interface provide additional flexibility.
From a power management perspective, the WM8400 includes two programmable 2MHz DC-DC step-down (Buck) converters, four low-dropout (LDO) regulators. The startup sequence and default voltages for the core regulators; DC-DC1, DC-DC2, LDO1 and LDO2 are selectable in hardware via external pins, and all regulators are also software programmable. The core regulators are intended to power the multimedia application processor sub-system while LDO3 and 4 are specifically designed to power the on-chip audio CODEC.
Paul Wilson, Wolfson's Power Management Product Line Manager comments, "Mobile handset designers are under intense pressure to deliver products that incorporate more high performance audio quality, into ever smaller form factors, with longer battery life than ever before. Wolfson is tackling this challenge head-on, with ultra low power consumption and integrated power management solutions like the WM8400 that help enhance the user experience by enabling significant power consumption reductions with no compromise in audio performance."