QSC PowerLight Series, Technical & Service Manual

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Technical Service Manual 85
PowerLight 6.0 II, PowerLight 6.0 PFC , and PowerLight 9.0 PFC
15 V
Node N273
“+15V_”
p. 4B7
15 V
Node N284
“-15V_”
p. 4B7
11 V
11 V HOT=250uA
@ 80 deg C.
The "HOT" threshold is 80C
Cutback begins at 100C and
full shutdown happens at 110C.
(+/- 3 degrees)
3
+
2
-
1
U1
2.5V-1%
VP
HOT
5V = 100 deg C.
C55
22u-25V
4
3
Fan idles at 10V up
to 60C. From 60C to
80C fan ramps from
10V to 24V. At 85C
fan V = 28V MAX.
(Note that SMPS can
also speed fan up.)
B3_N
_N_STEP
FAN_N
SNAPPER
PTC
5
+
6
-
7
2
3
1
VP
GAIN_RETARD
VN
1
2
Nominal I_SET = 3ma to 5ma.
Amp is fully on at I_SET>1ma.
Above 3ma fan is unaccellerated.
From 3ma to 1ma speed rises.
Below 1ma fan speed reduces
back linearily to normal speed.
I_SET
_V50
VP
Current gain: 22,460.
3.6 mA total set curent
results in 81A peak output.
Minumum at full cut-back is
250 uA or 5.6A output.
600ms delay to enable audio.
200ms delay to disable audio.
22u-25V
C1
17
SMPS_ON
DIFF_AMP_BIAS
MUTE
VN
G
D
S
PROTECT
_BOP
VN
VP
PSENABLE_K
PSENABLE_A
STANDBY_LED
_BOP
_BGND
70A = 5V
>5V = Current Limiting.
Total Gain = 16.85dB
5
+
6
-
7
5
+
6
-
7
3
+
2
-
1
Gain = 1/37.5
5
+
6
-
7
186V = 5V
-POL-
P_ISENSE
V_MON
MSP_VMON
_SPK_GND
N_ISENSE
MSP_IMON
I_MON
PowerLight 9.0
PFC
Management/Protection