Chapter 4. Euro 4D Supplement; Power Supply - Panasonic EURO 4 Chassis Technical Manual

3DQDVRQLF
Chapter 4
1.

POWER SUPPLY

The supply voltages on the EURO 4D chassis are
provided by two power supply circuits. The first of
which being the main power supply located on the
E-Board which uses
STR-F6654. The supply voltages produced by this
main power supply being used to power normal TV
operations as on the first generation EURO 4 chassis.
The second power supply circuit (discussed in
chapter 4 Section 2.) located on the W-Board uses the
integrated circuit STR-F6653, this power supply
being used to power the DVB decoder located on the
V-Board.
In-conjunction with the main power supply located on
the E-Board just mentioned, a standby power supply
is also used, however this standby power supply
normally located on the E-Board is now situated on
the W-Board. The benefits of using a standby power
supply results in a reduction in power consumption
when in standby mode.
The mains A.C. voltage input via connector M10 of the
M-Board is fed to the W-Board via the main TV
ON/OFF switch S802 to connector M11. The A.C.
voltage is then fed from the M-Board and connector
M11 to the W-Board and connector W1, where the
A.C. supply is fed to the standby transformer T802,.
From
W1
the integrated circuit
+12V
To
RL4801
To
W2
At the standby transformer T802 the A.C. supply splits
into three paths:
:
The first path sees the A.C. supply being fed to
the normally open contact of the standby relay
RL801.
:
The second path has the A.C. supply being fed
via the windings P1/P2 of the standby transformer
T802.
:
The Third path has the A.C. supply being fed to
the degaussing circuit and the positive temperature
co-efficient (PTC) resistor R802.
1.1. Standby Power Supply Circuit
The standby transformer T802 has the A.C. supply as
just mentioned being fed via the primary winding
P2/P1.
From the output of the secondary windings S2/S1 of
the standby transformer, a 7V supply is fed via resistor
R860, where the supply takes two paths.
2. The first path that the standby supply follows is
via capacitor C869 and rectifying diode D868,
this supply is then smoothed by capacitor C870.
This rectified and smoothed supply is then again
split into two paths.
5V
Standby
From
Pin 52
IC1101
42
EURO 4D Supplement
From
Q857 & D875
+B Protection