Sharp AY-XP9LSR Service Manual page 16

AYXP9LSR
1.21.2 Disabling auto restart function
By removing (cutting) jumper O (JP O) on the printed circuit board
(PCB), the auto restart function can be disabled.
2. Explanation of cluster circuit
The cluster unit generates cluster ions, which are circulated throughout the room by the air flow created by the blower fan (indoor unit fan motor) in
the air conditioner unit.
1) When microcomputer output turns "H," the Q11 output changes to "Lo," turning ON the SSR2 and applying 100 V to the cluster unit for the gener-
ation of cluster ions (positive and negative ions).
AC220-240V
Microcomputer output
3. Outline of PAM circuit
3.1. PAM (Pulse Amplitude Modulation)
The PAM circuit varies the compressor drive voltage and controls the rotation speed of the compressor.
The IGBT shown in the block diagram charges the energy (electromotive force) generated by the reactor to the electrolytic capacitor for the inverter
by turning ON and OFF.
Noise
AC
filter
230V
When the IGBT is ON, an electric current flows to the IGBT via the reactor (L1) and diode bridge (DB2).
When the IGBT turns OFF, the energy stored while the IGBT was ON is charged to the voltage doubler capacitor via the diode bridge (DB1).
As such, by varying the ON/OFF duty of the IGBT, the output voltage is varied.
12V
Q11
R39
Reactor L1
AC clock
detection
circuit
[PAM drive circuit]
Microcomputer (IC1)
PAM drive circuit block diagram
R34
SSR2
DB1
+
DB2
IGBT
drive
circuit
IGBT
2 – 10
Cluster unit
JPC1
1
1
JPC2
3 4
IPM
Compressor
Overvoltage
Compressor
detection
position
circuit
detector