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CTIA/OMTP Headset Ground Pole Switch
SGM2549D Autonomous Pole Position Fixing
www.sg-micro.com
PIN CONFIGURATIONS
(TOP VIEW) (TOP VIEW)
3
GND2
4
5
6
1
GM2
MIC
VCC
PHR
G
GM1
PIN DESCRIPTION
NOTE: I/O: Input or Output, G: Ground, P: Power for the circuit.
PIN
NAME TYPE FUNCTION
6 1 VCC P Power input to circuit in this IC.
5 2 PHR I/O
The output of voltage drop along the earphone returning ground path.
Signal picked at this node is used to suppress cross talk between 2
channels and between earphone driving and microphone output in
either analog domain or digital domain.
4 3 MIC P
Microphone bias and input switch node and parasitic power to
internal circuit if using microphone bias to power this IC. Connect to
the microphone bias of the circuit that this circuit works for.
3 4 GM1 IO
One possible grounding node. It is connected to MIC by default at
power up.
2 5 G G Ground of the internal circuit and ground for the earphone.
1 6 GM2 IO
Another possible grounding node. It is connected to G by default at
power up.