Top Port Analog Microphone

The WM7121 is a low-profile silicon analog microphone. It offers high Signal to Noise Ratio (SNR) and low power consumption and is suited to a wide variety of consumer applications. The WM7121 incorporates Cirrus Logic’s proprietary CMOS/MEMS membrane technology, offering high reliability and high performance in a miniature, low-profile package. The WM7121 is designed to withstand the high temperatures associated with automated flow solder assembly processes. (Note that conventional microphones can be damaged by this process.) The WM7121 top port microphone offers matched performance to the WM7132 bottom port microphone. The matched characteristics enable highly accurate sound pick up in opposite directions, suitable for noise cancellation and other DSP algorithms. The WM7121 variant offers a tighter tolerance on the microphone sensitivity, giving reduced variation between parts. This removes the need for in-line production calibration of part-to-part microphone variations.

Application Categories

Mobile Audio Devices, Speakers


  • High SNR (65 dB)
  • Low variation in sensitivity
    • ±1 dB tolerance (WM7121)
  • Matched pair with bottom port microphone WM7132
    • Matched sensitivity, roll-off and phase response
  • Low current consumption (190µA)
  • Analog output
  • Top port LGA package
  • 1.5V to 3.7V supply

Parametric Specifications

Port Top
SNR (dB) 65
AOP at 10% THD (dB SPL) 127
Sensitivity (dBV/Pa) -38
Sensitivity Tolerance +/- 1
Power Supply (V) 1.5-3.7
Supply Current (µA) 190
Package 3.76 x 2.95 x 1.10 mm

Technical Documents

WM7121 Product Datasheet

Apr 20, 2016, v4.1 : 681 Kb

1171 EV2 REV2 Example Configurations

Jul 1, 2014, v1.1 : 148 Kb

1700 EV1 REV1 Customer User Manual

Jul 1, 2014, v1.2 : 818 Kb

WM7121-1701-MS4-M-REV1 Schematic and Layout

Jan 1, 2013, v1.0 : 210 Kb

1171 EV2 REV2 Schematic and Layout

Aug 1, 2010, v1.0 : 375 Kb

Design Resources

CDB7121P Demonstration Board Datasheet

Nov 10, 2016, DS1126DB1 : 266 Kb

WAN_0284 General Design Considerations for MEMS Microphones

Jan 6, 2016, WAN0284 rev 1.2 : 506 Kb

WAN_0285 Microphone Power Gating

Nov 5, 2015, WAN0285 rev 1.1 : 508 Kb

WAN_0238 TDMA Noise Filtering

Nov 5, 2015, WAN0238 rev 1.1 : 338 Kb

WAN_0273 MEMS MIC Assembly and Handling Guidelines

Nov 5, 2015, WAN0273 rev 1.3 : 624 Kb

WAN_0290 An Introduction to MEMS Microphone Specifications

Jun 15, 2015, WAN0290 rev 1.0 : 538 Kb

Software and Tools

1700-EV1 Setup

n/a : 21112 Kb

WM7000 Setup

n/a : 1433 Kb



Comprehensive Solutions