Outline Of The Operation; Specification Of The Fan Control - Pioneer PDP-508XG Service Manual

5

4.5 OUTLINE OF THE OPERATION

4.5.1 SPECIFICATION OF THE FAN CONTROL

Block diagram
The internal fan cools down the MTB and Power blocks.
DIGITAL Assy
Module_Ucom
If an emergency signal is
detected, it will be
transmitted.
Main_Ucom
The Main microcomputer
controls the IF microcomputer
as a port expander.
IF_Ucom
MAIN Assy
Operation specifications
DAC output
HIGH
LOW
STOP
Notes:
• The operating temperature of the fan is higher than the ambient temperature, because the sensor temperature is read by
the microcomputer.
• If the critical values for signals are displayed in the address circuit, the fan may be activated or be rotated at higher speed
in response to values lower than the set temperature values shown above.
5
6
IO Assy
TEMP2
TEMP2
FAN_NG1
FAN_ON1
FAN_CONT1
34.5 ºC 37.5 ºC
PDP-508XG
6
7
Internal fan
Detection of
R
disconnection
FAN_VCC1
FAN_I_REG
0 to 12 V
VOLTAGE
CONTROL
40.5 ºC 43 ºC
7
8
A
B
C
D
Shutdown caused
by high temperature
E
62 ºC
F
35
8