Toshiba Camileo TDP-S20, Service Manual

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2
Operation of Power Supply
The APS-M526 power supply circuit can be divided into 2 main blocks (Fig.1)
1.the AC-DC converter, 2.the Time Sharing Multi-output control circuit.
These are shown as below.
AC
Input
14V
6-13V
COM
Fig. 1
1. The AC-DC Converter
The AC-DC converter can be further divided into sub-blocks as shown. (Fig. 2)
AC 6.5V
Input Output
Fig. 2
1) Input Line Filter
A switching power supply generates a lot of electromagnetic noise. The function of the AC line filter,
witch is made up of capacitors (eg. C101) and inductor choke (eg. L101), is to attenuate these noise so
that other equipments may not be affected.
Then, the power thermistor TH101 which restricts inrush current, and the surge absorber Z101 which
absorbes high voltage surge from the input lines. These are mounted on the input filter.
※
The fuse(F101) becomes open in order to protect other parts, when excessive current flows at
abnormal conditions.
AC-DC
Converter
Time
Sharing
Multi-output
Control Circuit
Lamp
Output
Input
Line
Filter
Power
Factor
Correction
Control
Circuit
Switching
Converter Rectifier &
Output Filter
Feedback
Control
Lamp
Output
6.5V
0V
3.4V
15V
0V
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