About The Protector - Pioneer DJM-900NXS Service Manual

5

5.5 ABOUT THE PROTECTOR

This unit monitors the voltages of the main power-supply ICs, using the voltage-monitoring circuit. As the ICPs (IC protectors)
are also used, some circuits cannot be monitored by the voltage-monitoring circuit when any wire for an ICP is broken.
(Circuits with thick frames in the figure below)
When any of the circuit blocks indicated in thick frames (located after the ICPs) in the figure below is in failure, also check for
a broken wire for the ICP.
Locations of the ICPs
MAIN ASSY
V+12D
ICP
non CIRCUIT
P1204: DEK1103
V+15A
V-15A
Names of the Power-Supply ICs
V+15A Before the ICP *1
MAIN
V+15A_1
V+15A_HP
V+15A_HP_1
V-15A Before the ICP *2
MAIN
V-15A_1
V-15A_HP
V-15A_HP_1
Diagnostic procedures when the wire for an ICP is broken
1. Unplug the AC power cord.
2. Check for any error, such as short-circuiting or defective parts, in the circuits subsequent to the ICP.
3. Repair the detective part.
4. Replace the ICP.
5
6
Voltage monitoring
OUTPUT RELAY
INPUT RELAY
5V DC/DC converter
3.3V DC/DC converter
1.2V DC/DC converter
34V DC/DC converter
HP CIRCUIT *1
ICP OUTPUT CIRCUIT *3
P1210: DEK1095
ICP
P1207: DEK1121
HP CIRCUIT *2
ICP OUTPUT CIRCUIT *4
P1209: DEK1096
ICP
P1208: DEK1121
After the ICP (P1210)
OUTPUT BLOCK *3&5
MAIN SEND
V+15A_O V+15A_SE
V+15A_SE
V+15A_SE_1
V+15A_BO
V+15A_M2
V+5A_REC
V+15A_M1
V+15A_M1_ICP
After the ICP (P1209)
OUTPUT BLOCK *4&5
MAIN SEND
V-15A_O V-15A_SE
V-15A_SE
V-15A_SE_1
V-15A_BO
V-15A_M2
V-5A_REC
V-15A_M1
V-15A_M1_ICP
6
7
SEND ASSY
INPUT ASSY
After the ICP (P1207)
INPUT BLOCK *6
MAIN INPUT
V+15A_IN V+15A_IN
After the ICP (P1208)
INPUT BLOCK *6
MAIN INPUT
V-15A_IN V-15A_IN
DJM-900NXS
7
8
SEND CIRCUIT *5
INPUT CIRCUIT *6
8
A
B
C
D
E
F
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