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 (MSM6250A).
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 (MSM6250A) 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.
3. TECHNICAL BRIEF
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Figure Audio Interface Detailed Diagram(MSM6250A)
Summary of Contents for U890
Page 1: ...Date April 2006 Issue 1 0 Service Manual Model U890 U890c Service Manual U890 U890c ...
Page 3: ... 4 ...
Page 20: ...3 TECHNICAL BRIEF 21 ...
Page 46: ...3 TECHNICAL BRIEF 47 Figure PM6650 2 Functional Block Diagram ...
Page 70: ...4 TROUBLE SHOOTING 71 4 2 SIGNAL PATH ...
Page 109: ...4 TROUBLE SHOOTING 110 CN600 50pin LCD connector CN901 C907 C911 FB901 FB902 ...
Page 115: ...4 TROUBLE SHOOTING 116 C226 C227 for MIC serial capacitor ...
Page 118: ...4 TROUBLE SHOOTING 119 Q400 Q401 Q402 VBATT GND ...
Page 139: ...Table 2 1 1 RF Block Component 6 BLOCK DIAGRAM 140 ...
Page 140: ...6 BLOCK DIAGRAM 141 6 2 Interface Diagram U890 Interface Diagram ...
Page 142: ...6 BLOCK DIAGRAM 143 Top Side ...
Page 143: ...6 BLOCK DIAGRAM 144 Bottom Side ...
Page 152: ... 153 8 pcb layout ...
Page 153: ... 154 8 pcb layout ...
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 163: ...9 CALIBRATION 164 9 3 HOT KIMCHI Example Choose_U890 ...
Page 164: ...9 CALIBRATION 165 Click APPLY button Click START button ...
Page 165: ...9 CALIBRATION 166 Click Run button to lunch RF AUTOTEST ...
Page 167: ... 168 ...
Page 191: ...Note ...
Page 192: ...Note ...