FSA8049 − 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

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Product Status/Pricing/Packaging

Product Product & Eco Status *Pricing Packaging & Packing Info **Package Marking Convention Qualification Support Compliance Certificates
0 FSA8049UCX Full Production
Green as of Jul 2011
$0.5352  Details
0.625 x 0 x 0mm

Line 1:M3&K
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ESD (HBM) :  7000  V
Moisture Sensitivity Level (MSL) :  1  
Max Reflow Temp :  260  


  • 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


  • Mobile Handsets
  • PMP/MP3 Players

Application Notes


Automatic Audio Jack Detection Demo

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