3.12 Headset Interface. LG KG291, KG290

3. TECHNICAL BRIEF

3.12 Headset Interface

This phone has 6 electrodes such as GND, AUXIP, AUXIN (this pin is floating), AUXOP,

JACK_DETECT, HOOK_DETECT. This type supports mono sound

Switching from Receiver to Headset Jack

If jack is inserted, JACK_DETECT goes from low to high.

Audio path is switched from receiver to earphone by JACK_DETECT interrupt.

Switching from Headset Jack to Receiver

If jack is removed, JACK_DETECT goes from high to low.

Audio path is switched from earphone to receiver by JACK_DETECT interrupt.

Hook detection

If hook-button is pressed, HOOK_DETECT is changed from high to low.

This is detected by AUXADC2.

And then hook is detected.

JACK_DETECT

C212

100p

20 R217

C213

100p

2V8_VMEM

2V8_VMEM

AUXOP_L_OUT

C218

AUXOP_L

10u

HEADSET_PATH_SEL

R270

100K

1

U210

NLAS5223BMNR2G

10

VCC NO2

2

NO1 COM2

9

3

COM1

4

IN1

5

NC1

IN2

8

NC2

7

GND

6

10u

AUXOP_R_OUT

AUXOP_R

C221

HEADSET_PATH_SEL

AUXIP

AUXIN

C224

27p

C225

27p

R228

C220

0.1u

0.1u

R225

3K

C226

10u

R229 1.5K

AUXOP_L_OUT

AUXOP_R_OUT

R226

R230

FM_ANT

33

33 L203

R216

1M

2V8_VMEM

VIN+ 3

R220

220K

5

VCC

U203

NCS2200SQ2T2G

1

GND

OUT

2

C214

1u

HOOK_DET

R224

NA

1800

L201 1800

L200 1800

1800

L202

C229

18p

VA202

NA

C230

27p

R233

1M

C231

39p

C232

27p

VA200

NA

C227

18p

VA201

NA

H

L

JACK_DETECT

INSERT

REMOVE

C233

NA

L204

J201

4.7uH

CLOSE TO EARJACK

Figure 3-14. HEADSET JACK INTERFACE

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Only for training and service purposes

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