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3. TECHNICAL BRIEF
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3.10.11.2 Audio Signal Processing & Interface
Audio signal processing is divided Uplink path and downlink path.
The uplink path amplifies the audio signal from MIC and converts this analog signal to digital signal
and then transmit it to DBB Chip (MSM6250).
This transmitted signal is reformed to fit in GSM & WCDMA Frame format and delivered to RF Chip.
The downlink path amplifies the signal from DBB chip (MSM6250) and outputs it to Receiver (or
Speaker).
The receive path can be directed to either one of two earphone amplifiers or the auxiliary output.
The outputs earphone1 (EAR1OP, EAR1ON) and Auxiliary out (AUXOP, AUXON) are differential
outputs. Earphone2 (EAR2O) is a single-ended output stage designed to drive a headset speaker.
The microphone interface consists of two differential microphone inputs, one differential auxiliary input
and a two-stage audio amplifier.
Figure 3.10.11.2-1 Audio Interface Detailed Diagram(MSM6250)
Summary of Contents for U880
Page 1: ...Date November 2005 Issue 1 0 Service Manual Model U880 Service Manual U880 ...
Page 20: ...3 TECHNICAL BRIEF 21 ...
Page 32: ...3 TECHNICAL BRIEF 33 Figure 3 5 6 1 GSM PA functional block diagram ...
Page 35: ...3 TECHNICAL BRIEF 36 Figure 3 5 10 1 Bluetooth system architecture ...
Page 50: ...3 TECHNICAL BRIEF 51 Figure 3 10 3 2 1 PM6650 Functional Block Diagram ...
Page 114: ...4 TROUBLE SHOOTING 115 Loud Speaker U502 U503 Amp ...
Page 118: ...4 TROUBLE SHOOTING 119 C200 C201 for MIC serial capacitor ...
Page 121: ...4 TROUBLE SHOOTING 122 Q404 Q403 Q402 VBATT GND ...
Page 128: ...5 DOWNLOAD 129 5 Choose a Module Image file after clicking on the Browse button ...
Page 143: ...6 BLOCK DIAGRAM 144 6 3 Interface Diagram U880 Interface Diagram ...
Page 145: ... 146 ...
Page 154: ... 155 8 PCB LAYOUT ...
Page 155: ... 156 8 PCB LAYOUT ...
Page 156: ... 157 8 PCB LAYOUT ...
Page 157: ... 158 8 PCB LAYOUT ...
Page 158: ... 159 8 PCB LAYOUT ...
Page 159: ... 160 8 PCB LAYOUT ...
Page 166: ...9 CALIBRATION 167 Click START button U880 U880_ver1 1 U880 U880 Click U880 ...
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Page 196: ...Note ...
Page 197: ...Note ...