Shivaki STV-24LEDGR7, Руководство по обслуживанию

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D-class power amplifier
R2A15120FA
PRELI
MINAR
Y
some
param
etric lim
its are
subjec
t to ch
ange.
CONFIDENTIAL
11-6.Soft mute
By using the CR filter circuit connected to MUTEL terminal, output signal can be smooth slope
when mute mode is turned on or off.
OUT
Output signal
MUTEL
MUTE
Control circuit
11-7. Protection control
Internal start-up timer
Internal
protect signal
PWM output
Terminal PROT
When unusual operation (Over Temperature, Over Current , Under Voltage) is detected,
R2A15120FA stops outputting PWM signal and makes output pins connect GND by
pull-down resistor (5k
Ω
) to prevent the IC from being destructed.
The restoring from a protection is performed automatically.
The time(Tpro) from protection state to normal mode is decided by built-in
capacitance value.(0.54sec)
The state of unusual operation can be confirmed with the terminal PROT(Protection:L).
Detect
H
：
Normal
L
：
Detect
MUTEL
Input signal
0V
AVCC
Normal Operation
Normal Operation
Under Protection
：
L:Pull-down to GND(VS)by 5k
Ω
)
Return Time:Tpro
Soft Mute
ON
Soft Mute
ON
Mute
Normal Operation
Normal Operation
(*)Return Time:T
pro
is proportional to the carrier frequency.
It is about 0.54sec when carrier frequency is 500kHz.
Tpro=270/fc[kHz]
fc[kHz]:Carrier frequency
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