wm8962 Wolfson Microelectronics plc, wm8962 Datasheet - Page 6

• Manufacturer Part Number: wm8962
• Description: Ultra-low Power Stereo Codec With Audio Enhancement Dsp, 1w Stereo Class D Speaker Drivers And Ground Referenced Headphone Drivers
• Manufacturer: Wolfson Microelectronics plc

Preliminary Technical Data
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DEVICE DESCRIPTION
The WM8962 is a low power audio CODEC offering a combination of high quality audio, advanced
features, low power and small size. These characteristics make it ideal for portable digital audio
applications with stereo speaker and headphone outputs such as games consoles, portable media
players and multimedia phones.
A flexible input configuration supports a single-ended stereo microphone interface and a digital
microphone interface. A boost amplifier is available for additional gain on the microphone inputs. A
programmable gain amplifier (PGA) with an automatic level control (ALC) function can be used to
maintain a constant microphone recording volume.
Stereo class D speaker drivers can provide >1W per channel into 8Ω loads, or 2W mono into a 4Ω
load. BTL configuration provides high power output and excellent PSRR.
Highly flexible output speaker boost settings provide fully internal level-shifting of analogue output
signals, allowing speaker output power to be maximised while minimising other analogue supply
currents, and requiring no additional components.
A dual mode (Level Shifting or Inverting Mode) charge pump generates split supplies for the
headphone output amplifiers allowing these to be ground referenced.
A DC servo to remove offsets from the headphone outputs, low leakage and a user controlled power-
up/power-down Control Sequencer provides powerful pop and click suppression mechanisms which
enable direct battery connection. These anti-pop/click mechanisms, and no requirement for any
external DC blocking capacitors to the headphone, result in a reduced external component count and
reduced power consumption in portable battery-powered applications.
The hi-fi quality stereo ADC and DAC uses a 24-bit, low-order over-sampling architecture to deliver
optimum performance. ADC and DAC operate at the same sample rate.
An audio enhancement DSP provides powerful benefits in audio processing. Three algorithms are
pre-programmed in the DSP. ReTune
playback path, including microphone, speaker and housing. Virtual Surround Sound widens the stereo
speaker audio image. High Definition Bass enhances low frequencies, improving the performance of
small speakers. Further audio enhancements are provided in a fix function DSP – 3D enhancement, a
5-band parametric equaliser, and a Dynamic Range Controller.
The WM8962 has a highly flexible digital audio interface, supporting a number of protocols, including
I2S, DSP, MSB-first left/right justified, and can operate in master or slave modes. PCM operation is
supported in the DSP mode. A-law and μ-law companding are also supported. Time division
multiplexing (TDM) is available to allow multiple devices to stream data simultaneously on the same
bus, saving space and power.
The WM8962 provides two integrated PLLs and one Exact Fractional Synthesis (EFS) FLL to
generate internal and external clock signals. The SYSCLK (internal system clock) provides clocking
for all internal functions. SYSCLK can be derived directly from the MCLK pin, or else using one of the
PLLs or the FLL. All MCLK frequencies typically used in portable systems are supported for sample
rates between 8 kHz and 96 kHz. The ADC and DAC must be configured to operate at the same
sample rate. A flexible switching clock for the class D speaker drivers (synchronous with the audio
DSP clocks for best performance) is also derived from SYSCLK.
To allow full software control over all its features, the WM8962 supports 2-wire (I2C) and 3- or 4-wire
(SPI) serial control interface modes, with full read-back capability on all registers. The WM8962 is fully
compatible with, and an ideal partner to, a wide range of industry standard microprocessors,
controllers and DSPs. Unused functions can be disabled via software to save power, while low
leakage currents extend standby and off time in portable battery-powered applications.
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flattens the frequency response of the full record and/or
Product Brief, July 2010, Rev 2.0
WM8962
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