3. TECHNICAL BRIEF
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3.8.6 Wideband CODEC
The MSM6250A device integrates a wideband voice/audio CODEC into the mobile station modem
(MSM). The CODEC supports two differential microphone inputs, one differential earphone output, one
single-ended earphone output, and a differential analog auxiliary interface on two single-ended
earphone output. The CODEC integrates the microphone and earphone amplifiers into the MSM6250A
device, reducing the external component count to just a few passive components.
The microphone (Tx) audio path consists of a two-stage amplifier with the gain of the second stage set
externally. The Rx/Tx paths are designed to meet the ITU-G.712 requirements for digital transmission
systems.
3.8.7 Vocoder Subsystem
The MSM6250A device’s QDSP4000 supports AMR vocoder. In addition, the QDSP4000 has modules
to support the following audio functions: DTMF tone generation, DTMF tone detection, Tx/Rx volume
controls, Tx/Rx automatic gain control (AGC), Rx Automatic Volume Control (AVC), EarSeal Echo
Canceller (ESEC), Acoustic Echo Canceller (AEC), Noise Suppression (NS), and programmable, 13-
tap, Type-I, FIR, Tx/Rx compensation filters. The MSM6250A device’s integrated ARM7TDMI
processor downloads the firmware into the QDSP4000 and configures QDSP4000 to support the
desired functionality.
3.8.8 HKADC
TheMSM6250A device has an on-chip 8-bit analog-to-digital converter (ADC) which is intended to
digitize DC signals corresponding to analog parameters such as battery voltage, temperature, and RF
power levels. The MSM6250A device has six analog input pins which are multiplexed to the input of
the internal HKADC.
3.8.9 General-Purpose Input/Output Interface
The MSM6250A device has general-purpose bidirectional input/output pins. Some of the GPIO pins
have alternate functions supported on them. The alternate functions include USB interface, additional
RAM, ROM, general-purpose chip selects, parallel LCD interface, and UART interface.
3.8.10 UART
There are three UARTs in the MSM6250A ASIC:
• UART1 for data
• UART2 (can be used for USIM interface)
• UART3 (can be used for PM SBI interface)
3.8.11 USB
The MSM6250A device integrates a universal serial bus (USB) controller that supports both
unidirectional and bidirectional transceiver interfaces. The USB controller acts as a USB function
communicating with the USB host. The USB controller also supports digital audio through USB
interface and connects directly to the QDSP4000 for the audio processing.
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 ...