LG KG280 Service Manual - Page 33

3. TECHNICAL BRIEF 3.10 Microphone The microphone is placed to the Rear cover and contacted to main PCB. The audio signal is passed to VINNORP and VINNORN pins of AD6720. The voltage supply VMIC is output from AD6720, and is a biased voltage for the VINNORP. The VINNORP and VINNORN signals are then A/D converted by the voiceband ADC part of AD6720.The digitized speech (PCM 8KHz ,16KHz) is then passed to the DSP section of AD6720 for processing (coding, interleaving etc). MAIN MIC 2V5_VMIC VINNORP VINNORN R219 1K R220 1K C227 39p ECTH0004806 C226 22uF FB201 SFBH0008102 R221 100ohm C228 39p R222 100ohm C230 0.1u R223 2.2K R232 NA R233 C229 NA 39p BOS-T1342SDN3-LH SUMY0010509 MIC200 1 2 C231 NA C232 NA VA202 EVLC18S02003 VA203 EVLC18S02003 Figure 3-12. Connection between Microphone and AD6720 3.11 Main Speaker AIN1P AIN1N N17 P17 AIN2N AIN2P R17 L16 AIN3P AIN3N L17 H16 AOUT1P AOUT1N K17 P15 AOUT2P2 AOUT2P1 R16 R15 AOUT2N1 AOUT2N2 P14 H17 AOUT3P AOUT3N J17 G11 TDO_ABB TMS F13 E13 TDI_ABB F12 AUXOP AUXON SPKP_P AUXOP AUXON C131 C132 C133 C134 39p 39p 39p 39p R119 4.7 R123 4.7 R125 NA C130 39p C135 39p VINNORP VINNORN AUXIN AUXIP REC_P REC_N C136 39p D D33 D34 D35 D11 LGE Internal Use Only - 34 - Copyright © 2007 LG Electronics. Inc. All right reserved. Only for training and service purposes