The WM8940 is a low power, mono codec with integrated support for a differential or single ended mic, and includes drivers for speakers or headphone and mono line output. Advanced Delta Sigma converters are used along with digital decimation and interpolation filters to give high quality audio at sample rates from 8 to 48 ks/s. A selectable high pass filter and four fully programmable notch filters are available in the ADC path. An advanced mixed signal ALC function with noise gate is provided, while readback of PGA gain during ALC operation is supported. The digital audio interface supports A-law and μ-law companding. An on-chip PLL is provided to generate the required main clock from an external reference clock. The PLL clock can also be output if required elsewhere in the system.



  • Audio sample rates: 8 to 48 kHz
  • Support for differential or single-ended mic
  • On-chip PLL
  • 2.5 V to 3.6 V (digital supplies: 1.71 V to 3.6 V)
  • 4x4mm QFN package

Parametric Specifications

Channels In 1
Channels Out 1
DAC THD+N (dB) -84 (THD)
ADC THD+N (dB) -80 (THD)
Analog Power Supply (V) 2.5-3.6
Digital Power Supply (V) 1.71-3.6
Logic Power Supply (V)
Operational Power Consumption (mW) 14.3-216.8
Package 24 QFN

Technical Documents

WM8940 Product Datasheet

Jan 1, 2022, v4.4 : 1.2 Mb

6162 EV1 REV2 Schematic and Layout

Oct 12, 2018, v1.0 : 1.1 Mb

Design Resources

WAN-0118 Guidelines

Sep 1, 2014, WAN_0118 rev 2.5 : 740 kb

WAN_0197 Improving the PSRR in Wolfson CODECs

Jun 1, 2008, WAN0197 rev 1.0 : 130 Kb

Software and Tools


Jan 14, 2021, v3.12.0.5 : 43.2 Mb


Comprehensive Solutions