QSC PowerLight3 Series - PL380 Main Circuit Board, Detailed View; PL380 Input Board, Main Circuit Blocks Shown

PL3 Series Service Manual 59
TD-000274-00 Rev. A
Capacitor voltage
protection
Capacitor voltage
protection
Fan speed
control
Fan speed
control
DC
shutdown
DC
shutdown
Service
plug-in
Service
plug-in
+15V
regulator
+15V
regulator
Ch 2
high-frequency
voltage mute
Ch 2
high-frequency
voltage mute
-15V, ±5V
supply
-15V, ±5V
supply
Relay timer &
stby/mute control
Relay timer &
stby/mute control
Ch 1
high-frequency
voltage mute
Ch 1
high-frequency
voltage mute
Ch. 1 limiter
control system &
protection limiter
Ch. 1 limiter
control system &
protection limiter
Ch. 2 feedback
compensation
& modulator
Ch. 2 feedback
compensation
& modulator
Limiter control:
PS current
Limiter control:
PS current
DataPort
Vmon, Imon,
Temp (Ch. 2)
DataPort
Vmon, Imon,
Temp (Ch. 2)
Ch. 2 overcurrent
feedback
Ch. 2 overcurrent
feedback
Ch. 2 gate drive
control & dead
time isolation
Ch. 2 gate drive
control & dead
time isolation
Ch. 1 gate drive
control & dead
time isolation
Ch. 1 gate drive
control & dead
time isolation
Ch. 1 overcurrent
feedback
Ch. 1 overcurrent
feedback
Ch. 1 clip
±14V power
Ch. 2 limiter
control system &
protection limiter
Ch. 2 limiter
control system &
protection limiter
Crystal-divider
clock circuit
Crystal-divider
clock circuit
Temperature
compensated
modulator
clamp reference
Temperature
compensated
modulator
clamp reference
Audio mute
Clean ±5V supply
Ch. 1 feedback
compensation
& modulator
Ch. 1 feedback
compensation
& modulator
Ch. 2 clip
Ch. 1 clip
limiter drive
Ch. 1 m/f XLR
inputs, buffer
& HP filter
Ch. 1 clip
limiter switch
Ch. 1 HP
filter switch
Mode
switch
Gain/
sensitivity
switch
Ch. 2 clip
limiter switch
Ch. 2 HP
filter switch
Ch. 2 m/f XLR
inputs, buffer
& HP filter
Ch. 1 & 2
pot buffers
Ch. 2 clip
limiter
drive
BMF
flag
±15V
supply
Ch. 2 gain/
sensitivity resistors
Ch. 1 gain/
sensitivity resistors
+5V supply
Ch. 1 & 2 log
amps, signal
LED drivers
PL380 main circuit board,
detailed view
PL380 input board, main
circuit blocks shown