Audio Jack Detection and Configuration, MIC / GND Cross Point Switch

The FSA8049 is an audio jack detection switch for 3- or 4-pole accessories. The FSA8049 detects the locations of ground (GND) and microphone (MIC) poles on the audio plug and automatically routes them to the appropriate connections. This allows the end user to plug accessories, such as headsets with different audio pole configurations, into the mobile device and have them operate correctly.

■ Detects 3- or 4-pole audio accessories

■ Detects polarity of GND and MIC on 4-pole plugs

■ Automatically routes GND and MIC to audio jack terminals


  • Detection: Audio Plug GND & MIC Polarity
  • VDD: 2.5 to 4.4V
  • THD (MIC): 0.002% Typical
  • ESD (IEC 61000-4-2 Air Gap): 15kV
  • Operating Temperature: -40°C to 85°C
  • Package: 9-Ball WLCSP 3x3 Array, 0.4mm Terminal Pitch, 250µm Ball
  • Top Mark: M3
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Product Product &
Eco Status
Unit Price/
1K Order
Packing Method Convention Package Marking
FSA8049UCX Full Production
Green as of Jul 2011

WL-CSP 9L  -  Details
0.625 x 0 x 0mm,  TAPE REEL

PDF WL-CSP 9L  Drawing
Last Update: Jan 2015 PDF WLCSP 1.16x1.16, Packing Drawing
Last Update: Feb 2015 PDF WLCSP Tape and Reel Packing Drawing
Last Update: Nov 2015
Line 1M3&K

Line 2&. (Pin One)
&2 (2-Digit Date Code)
&Z (Plant Code)

FIT 0.9 @55°C
change temp

ESD (HBM) 7000V

Moisture Sensitivity Level (MSL) 1

Max Reflow Temp 260


If there is no sample button displayed at the top of the page, please contact one of the Fairchild distributors or your local sales office to obtain samples.
* Click here for further top mark packaging information for FSA8049

  • Mobile Handsets
  • PMP/MP3 Players

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