w

WM2002

Stereo Headphone Driver with Wolfson

Ambient Noise Cancellation

WOLFSON MICROELECTRONICS plc

Product Brief, September 2013, Rev 4.1

Copyright

2013 Wolfson Microelectronics plc

DESCRIPTION

The WM2002 is a low power, high quality stereo headphone

driver, delivering Wolfson’s patented ambient noise cancellation.

The WM2002 supports analogue playback or voice input, and

analogue microphones for noise cancellation.

Designed for incorporation within a stand-alone headset or

headphone, the Wolfson ANC noise cancellation engine

performs ambient noise cancellation during a voice call or during

music playback.

The

WM2002

provides

integrated

power

management,

comprising a DC-DC converter, Charge Pump and LDO

Regulators. Different power supply configurations can be

supported, including operation from a single cell AAA or AA

battery, and other configurations using externally regulated

supplies.

System clocking is achieved using a crystal-controlled on-chip

oscillator. An external clock can be connected directly, if

available.

The WM2002 is configured using programmable settings stored

in an integrated non-volatile memory. The configuration stored in

the OTP memory is enabled automatically at start-up. If

required, the WM2002 can also be configured using register

control accessed using a 2-wire serial control interface.

FEATURES



Wolfson Ambient Noise Cancellation (ANC)

-

>30dB (peak), 25dB (typical) ambient noise reduction*

-

Wide noise cancellation bandwidth (40Hz to 4kHz)*

-

* depending on acoustic configuration

-

Up to 3 banks of ANC coefficients can be programmed to

support different operating conditions



Audio inputs

-

Up to 10 analogue noise cancellation microphones

-

2 single-ended or 1 differential line input per channel



Headphone driver (LDO4VOUT = 1.8V)

-

45mW per channel into 16

 load

-

22mW per channel into 32

 load

-

Single-ended or differential (BTL) drive configuration

-

-82dB THD+N for differential (BTL) drive



Integration

-

On-chip DC-DC boost converter, charge-pump and LDOs

-

Flexible power supply options, including single cell battery

(1 x AAA battery)

-

Internal crystal oscillator



Miscellaneous

-

Monitor pin to select mute / talk-through modes

-

LED driver

-

Tone generator for audible status indication

-

Pop and click noise protection circuit

-

RFI suppression

-

48-pin QFN package (7 x 7 x 0.75mm, 0.5mm pitch)

APPLICATIONS



“Pod-style” stereo ear-buds, headsets, headphones with

ANC



“Supra-Aural” stereo headphones with ANC



Mono/Stereo Bluetooth headsets with ANC