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5
KDC-BT7539U/BT8041U
/BT8141UY/BT838U
Ref. No.
Application / Function
Operation / Condition / Compatibility
Q121
B.U Detected SW
When Q121’base gose Hi, B.U voltage is detected.
Q122
Surge Detect SW
When Q122’base goes Hi, Surge voltage is detected.
Q123
ACC Detect SW
When Q123’base gose Hi, Acc voltage is detected.
Q141,144
P-CON SW
When Q144’base goes Hi, AVR outputs 14V.
Q142,143
P-CON Protect
Protect Q141 by turning on when P-CON output is grounded.
Q145,146
Power Antenna SW
When Q146’base goes Hi, power antenna switch outputs 14V.
Q151
Small-lamp Detect SW
When Q151’base goes Hi, Small-lamp is detected.
Q321,322
AM+B SW
When Q322’base gose Hi, AM+B is outputs.
Q331
AGC CONTROL (for SPE. ANA.)
AGC GAIN CONTROL
Q401~406
Pre-out mute SW
When a base gose Hi, Pre-out is set to mute.
Q407,408
Pre-out mute driver
When a base gose Lo, mute driver is turned on.
Q602,603
LEVEL SHIFT
System
μ
-com (5V) to Sub
μ
-com (3.3V)
Q680
Invertor
When a base gose Hi, BT RESET is ON.
Q681,682
PANEL +5V SW
When Q682’base gose Hi, PANEL +5V is outputs.
Q683,684
LEVEL SHIFT
CD mechanism (3.3V) to Sysytem
μ
-com (5V)
Q702,703
3.3V_AVR_for_IC700 (
fl
ash_type)
When base of Q702 is “H”, 3.3V_On.
Q704
Decoder SRAM standby control Buffer
When base of Q704 is “L”, SRAM_STBY.
Q705
CD “LOE_LIM” SW_Buffer
When base of Q705 is “H”, Loading_End.
Q900
L.P.F
L.P.F for BT Output (Rch)
Q901
L.P.F
L.P.F for BT Output (Lch)
●
CD PLAYER UNIT (X32-6130-00)
Ref. No.
Application / Function
Operation / Condition / Compatibility
IC3
4ch BTL Driver
Driver for focusing & tracking coil, driver for sled & spindle motor, and operation
for disc loading & ejection.
IC4
Servo DSP with built-in Audio DAC
With built-in MP3/WMA/AAC decoder and 1M-bit-SRAM.
IC5
D1.5V REG.
Power supply for digital 1.5V.
IC6
D3.3V REG.
Power supply for digital 3.3V.
IC11
BU1.5V REG.
Power supply for back-up 1.5V.
Q1
APC (Auto Power Control)
Drives LD (Laser Diode).
Q13
Inverter
Inverts ZDET signal.
D2
Laser Diode Protection
Prevents reverse bias which is applied to laser. Laser destruction prevention.
D3,4
Static Electricity Countermeasure
Prevents malfunction by static electricity.
COMPONENTS DESCRIPTION