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QQ
3 7 63 1515 0
Ref. No.
Application / Function
Q4,5
Mute
Q8~11
Gate driver
Q12,13,19,20
DC/DC converter
Q25,26,28,42
AVR
Tracking when ±15V AVR is turned OFF
Q29,30
Q37,38
DC/DC converter pulse ON/OFF control
Q151
Mute
Q400,403
Dclass amplifier switch
Q401,402
Pulse amplification, shaping and
Q404~409
level shift
Q414,415,417
Q410~413
Power amplification
Q416
HB 15V AVR
Attenuation circuit to attenuate
Q603
input signal by 1.5dB
Q604~607
Current-voltage conversion
Q608~611
Latch circuit
TE
L 13942296513
Resonance detection and protection technique
• Measures against SP terminal's shortening
Since resonance voltage is generated with an output LC filter,
during the time after shortening until a short circuit current is
generated, detect resonance voltage and turn D-POWER off.
L
Current
Impedance and terminal contact resistance are in-
herent in the circuit.
Therefore, resonance voltage is generated at both
ends of a shorted C.
www
But resonance voltage occurs less when shorten-
ing at a low output voltage point.
.
COMPONENTS DESCRIPTION
Generates mute drive signal and turns off LED.
Gate driver in DC/DC converter FET
DC/DC converter switching
±15V AVR
Matches the trailing edge of '-15V' AVR with that of '+15V' AVR.
ON or OFF DC/DC converter drive waveform.
Turns off audio signal.
Turns on or off Dclass amplifier.
Generates signal that drives the final FET in Dclass.
High-current switching in Dclass.
Stacking AVR to obtain High+B for Dclass.
Attenuates output when temperature in the set becomes too high.
Converts current to voltage to detect overcurrent and sends it to the comparator.
Detects overvoltage in output and retains the current.
CIRCUIT DESCRIPTION
Resonance voltage
generating point
Output
C
Short
x
ao
u163
y
i
2 9
8
Operation / Condition / Compatibility
Q Q
3
6 7
1 3
1 5
• Circuit description
Resonance voltage caused by shortening is detected through
a high pass filter.
Filter characteristics is 2kHz cut-off and -18dB attenuation.
q At 100Hz, voltage is attenuated up to -59dB of 10.6V and
peak voltage becomes 12mV.
w At 200Hz, voltage is attenuated up to -44dB of 10.6V and
peak voltage becomes 6.7mV.
e Since resonance voltage frequency is 3.7kHz, voltage does
not attenuate.
Therefore, only resonance voltage can be detected.
10V
10V
100k
100k
co
0.01u 0.033u 0.033u
Output
IC64
.
(1/2)
KAC-8103D
9 4
2 8
0 5
8
2 9
9 4
2 8
m
2.2k
IC64
(2/2)
1k
15k
9 9
9 9
to Dclass,
power off
control
15V
3
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