Products : CODECs

Stereo CODEC
WM8980_BlockDiagram.gif
FEATURES
  • Stereo CODEC:
  • DAC SNR 98dB, THD -84dB (’A’ weighted @ 48kHz)
  • ADC SNR 90dB, THD -84dB (’A’ weighted @ 48kHz)
  • On-chip Headphone Driver with ‘capless’ option
  • 40mW output power into 16 Ohmn / 3.3V SPKVDD
  • 1W output power into 8 Ohmn BTL speaker / 5V SPKVDD
  • Capable of driving piezo speakers
  • Stereo speaker drive configuration
  • Mic Preamps:
  • Stereo Differential or mono microphone interfaces
  • Programmable preamp gain
  • Psuedo differential inputs with common mode rejection
  • Programmable ALC / Noise Gate in ADC path 
  • Low-noise bias supplied for electret microphones

  • Other Features: 
  • Integrated 0-6dB video buffer with LPF filter and clamp 
  • Enhanced 3-D function for improved stereo separation
  • Digital playback limiter
  • 5-band Equaliser (record or playback)
  • Programmable ADC High Pass Filter (wind noise reduction)
  • Programmable ADC Notch Filter
  • Aux inputs for stereo analog input signals or ‘beep’
  • On-chip PLL supporting 12, 13, 19.2MHz and other clocks
  • Low power, low voltage
  • 2.5V to 3.6V (digital core: 1.71V to 3.6V)
  • 6x6mm 40-pin QFN package
DESCRIPTION

The WM8980 is a low power, high quality stereo CODEC with integrated video buffer designed for portable applications such as multimedia phone, digital still camera or digital camcorder.

The device integrates preamps for stereo differential mics, and includes drivers for speakers, headphone and differential or stereo line output. External component requirements are reduced as no separate microphone or headphone amplifiers are required.

An integrated video buffer is provided which has programmable gain from 0-6dB (6-12dB unloaded), sync-tip clamp and a 3rd order input low pass filter for signal re-construction.

Advanced on-chip digital signal processing includes a 5-band equaliser, a mixed signal Automatic Level Control for the microphone or line input through the ADC as well as a purely digital limiter function for record or playback. Additional digital filtering options are available in the ADC path, to cater for application filtering such as ‘wind noise reduction’.

The WM8980 digital audio interface can operate as a master or a slave. An internal PLL can generate all required audio clocks for the CODEC from common reference clock frequencies, such as 12MHz and 13MHz.

The WM8980 operates at analogue supply voltages from 2.5V to 3.3V, although the digital core can operate at voltages down to 1.71V to save power. The speaker outputs and OUT3/4 line outputs can run from a 5V supply if increased output power is required. Individual sections of the chip can also be powered down under software control.