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3-13
ONE POINT REPAIR GUIDE
NO SOUND
There is no sound output in the USB FUNCTION, repair the set according to the
following guide.
5-3. IN THE USB FUNCTION
5-3-1. Solution
Please check and replace IC501 on MAIN board & IC302 on USB board.
5-3-2. How to troubleshoot (Countermeasure)
1) Check +5V_USB to USB board.
If the USB LED are turned on, the voltage is okay, if so not, check +5.6 V to pin6 of CN302.
2) Check USB D1± or USB D2± from MAIN board to USB board.
a. Check 2.0_D1±signals(pin U7, U8 ) or 1.1_D1± signals(pin A7, A8 ) to IC501.
b. Check USB± signals to CN302(pin1, 2, 4, 5).
If there is any trouble, check the power for each IC. The power is normal but , if the signal waveform to
the IC is distorted or no signal, replace it with a new one.
3) Check if “Digital audio AMP block” on item 5-2 is normal.
5-3-3. Service hint (Any picture / Remark)
D- to pin 1&4 of CN302
D+ to pin 2&5 of CN302
< Waveform of USB D± signal >
< USB function signal
fl
ow >
PWM
TAS5548
TAS5624LA
FR,FL
Woofer
12.288 MHZ
TAS5624LA
DSP IC501
MLC3730
176PIN BGA
USB1_D±
USB2_D±
Interrupt
controller
CDROM x8 speed
Decoder
NAND Controller
within BCH codec
14bits ECC
GDMA 3ch
ADC (12bit*5ch)
Timer, Watchdog
GPIO (72 Max)
SPI 4ch (Max)
RTC & Wake up
UART 4ch (Max)
I2C 2ch
SDHC-SDIO 4ch (Max)
USB 2.0 OTG
SRAM (10K)
Main Processor
Audio DSP-0
GDMA 2ch
I2S (7.1ch)
SPDIF (Rx, Tx)
ADPCM
PLL
Clock Controller
Reset Controller
Test Controller
Audio DSP-1
USB 1.1
Host/Device
ARM
926EJS
16KB
I-Cache
16KB
D-Cache
400Mhz
DSP
133Mhz
SRAM29KB
I-Cache 8KB
D-Cache 8KB
DSP
133Mhz
SRAM29KB
I-Cache 8KB
D-Cache 8KB
Boot ROM (20KB)
SDRAM
Controller
Содержание CM4550
Страница 13: ...2 2 ...
Страница 17: ...A60 4 SPEAKER SECTION 4 1 FRONT SPEAKER CMS4550F ...
Страница 18: ...2 9 A90 4 2 SUBWOOFER SPEAKER CMS4550W ...
Страница 19: ...2 10 ...
Страница 50: ...4 USB 13 USB_5 V D D 14 3 31 IC501 PIN A8 IC501 PIN A7 ...
Страница 51: ...3 32 ...
Страница 66: ...3 61 3 62 2 MAIN P C BOARD TOP VIEW BOTTOM VIEW ...
Страница 67: ...3 63 3 64 3 FRONT P C BOARD TOP VIEW BOTTOM VIEW ...