Power Requirements; Pcb Explanations; Power Board (16Pw07 E3) - VESTEL SAT 3600 Service Manual

SERVICE MANUAL

POWER REQUIREMENTS

Power measurements are for a board configured according to the included Bill of Materials while playing a
typical DVB channel.
Voltage
LNB_SUPPLY_IN (13V, 18V)
+30V
+12V
+3V3
Voltage
LNB_SUPPLY_IN (13V, 18V)
+30V
+12V
+3V3

PCB EXPLANATIONS

INTRODUCTION
DVB-S (digital satellite receiver) is designed with ST chipset. The technical information of
the receiver will be explained as three parts in the following pages: Power Board, Main Board
and Front Panel Board.

POWER BOARD (16PW07 E3)

The TOPSwitch concept is used for power supply. TOP 233Y (IC1) is designed to work
until 50 Watts in family of TOPSwitch_FX with 5 pins. The receiver works between 85 and 265
VAC mains voltage by using TOP 233Y in SMPS (Switch Mode Power Supply). The secondary
voltage regulation is adjusted by changing the duty cycle of drain signal according to the
feedback voltage, which is got from the secondary side of transformer. The feedback voltages
are 3.3V and 5V. This is connected to the comparator pin of TOP 233Y (IC1-pin1) via IC12
(Optocoupler). The comparator pin also protects the box against short circuits and overload. The
Vcc voltage of IC1 is between 2V –3V at pin2. The TOP 233Y works at a fixed frequency. This
frequency is fixed by RC oscillator at pin1. The pin3 and pin 4 are ground and the pin5 is drain
of MOSFET, which is inside the TOP 233Y.
16MB07 E3 Board
Power Consumption
+5V
+5V
Rev 1.0 21.10.02 16:23
Current mA
-----
1mA
30mA
130mA
-----
Current mA
500mA (max)
1mA
100mA
200mA
960mA
Power
Watts
-----
----
Power
Watts
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