Components Description - Kenwood KDC-348U Service Manual

KDC-348U/4751SD/BT41U/BT648U
/U4549/U4549SD/U549BT/X395/X695
● ELECTRIC UNIT (X34-696x-xx)
Ref. No.
IC1 Power Supply IC
IC21 3.3V AVR IC
IC51 SW REG
IC71 Hi-side SW
IC201 System μ-COM
IC202 Reset IC
IC203 E2PROM
IC261 iPod Authentication IC
IC301 3.3V to 5V
IC401 E-VOL
IC501 ATomIC RDS
IC601,602 3.3V to 5V
IC801 Power IC
IC802 3.3V to 5V
IC901 BT LPF
IC902 3.3V AVR
IC921 Switch IC
Q1,2 SERVO+B AVR
Q3,4 Control SW for SERVO+B
Q5,6 Control SW for IC1
Q7,8 Control SW for IC1
Q9,10 Control SW for IC1
Q51 FREQ CONT SW for IC51
Q91,92 4V PREOUT+B AVR
Q93,94 CONT SW for 4V PREOUT+B
Q101 ACC DET
Q102 Surge DET
Q103 BU DET
Q104 Mute CONT
Q301 PAN3.3V SW
Q302 SW3.3V SW
Q701,702 Pre-out Mute SW
Q703,704 Pre-out Mute SW
Q705,706 Pre-out Mute SW
Q707,708 Mute Driver for Pre-out
Q921 MIC SW CONT
Q951 SD3.3V SW
4

COMPONENTS DESCRIPTION

Application / Function Operation / Condition / Compatibility
Outputs 5Vx2, 8V, 8.3V, 10.3V, P-CON, P-ANT.
Power supply for BU+3.3V to μ-COM.
Power supply for D+5.1V to USB and panel.
USB over-current detection.
Controls FM/AM tuner, CD mechanism, panel, volume.
Lo when detection voltage goes below 2.8V.
For log memory.
For Apple authentication.
Level shift.
Controls the source and volume.
Tuner IC.
Level shift.
Amplifi es the front L/R and the rear L/R to 50W maximum.
Level shift.
Bluetooth output low pass fi lter.
Power supply for BT/SD+3.3V.
MIC switching signal (Panel microphone/ Rear microphone)
When Q2's base goes Hi, AVR outputs 7.5V.
ON when Q3's base goes Hi.
ON when Q5's base goes Hi.
ON when Q7's base goes Hi.
ON when Q9's base goes Hi.
1.1MHz when the base goes Lo, 1.7MHz when the base goes Hi.
When Q92's base goes Hi, AVR outputs 12V.
ON when Q94's base goes Hi.
ON when the base goes Hi during ACC is applied.
When the base goes Hi, surge voltage is detected.
ON when the base goes Hi during BU is applied.
ON when the base goes Hi.
ON when the base goes Lo.
ON when the base goes Lo.
When one of 2 bases goes Hi, pre-out is muted.
When one of 2 bases goes Hi, pre-out is muted.
When one of 2 bases goes Hi, pre-out is muted.
ON when the base goes Lo.
Rear MIC when the base goes Lo, panel MIC when the base goes Hi.
ON when the base goes Lo.