Circuit Descriptions, Abbreviation List, and IC Data Sheets
EN 90 LC4.41E AA9.
9.3 Power Supply Unit
9.3.1 Description
The power supply is a bought module, that consists of the
following parts:
• the AC mains input with fuse;
• a separate stand-by supply;
• the mains harmonic circuit;
• the mains rectifier.
The power supply provides the following output voltages:
• 3.3V for the UOCIII, Scaler and other digital circuits;
• unregulated 12V, which is converted to regulated 5V, 8V,
and 12V;
• a so-called bolt-on supply, which provides 12V for bolt-on
devices (not covered in this manual).
9.3.2 States and Sub-states of the Power Supply
The power supply has three different states. Each of these
states has a couple of sub-states:
1. POWER OFF:
a. PASSIVE OFF:
The set is switched off completely, the mains cable is
disconnected. When the mains is re-connected, the set
switches to the last STAND-BY status.
b. ACTIVE OFF:
The set is connected to the mains, and consuming a
minimum amount of power. This sub-state is similar to
NORMAL STAND-BY, but all LED indicators are off.
Switch to the ON or STAND-BY mode with the
POWER ON/OFF button (in the NAFTA region also
with the STAND-BY KEY of the RC).
2. STAND-BY:
a. NORMAL STAND-BY:
Only Hercules and NVM are connected to the power
(+3V3STBY), other circuits are disconnected. The LED
lights red. The signal from a control port can switch the
set OFF or ON.
b. SEMI STAND-BY:
Only on DVB sets. In this state the LED lights red.
+3V3STBY, +12VUNREG, and +12V iBOZ remain ON
for a certain time. After that time only +3V3STBY stays
ON, only powering Hercules and NVM, so the set is in
NORMAL STAND-BY.
3. POWER ON:
This is the normal operating mode. All power supply lines
are available. All circuits are active. From this mode the set
can switch to NORMAL STAND-BY, SEMI STAND-BY,
OFF, or PROTECTION.
9.4 Abbreviation List
0/6/12 SCART switch control signal on A/V
board. 0 = loop through (AUX to TV), 6
= play 16:9 format, 12 = play 4:3
format
1080i 1080 visible lines, interlaced
1080p 1080 visible lines, progressive scan
2CS 2 Carrier Sound (or 2 Channel Stereo)
480i 480 visible lines, interlaced
480p 480 visible lines, progressive scan
ACI Automatic Channel Installation:
algorithm that installs TV channels
directly from a cable network by
means of a predefined TXT page
ADC Analogue to Digital Converter
AFC Automatic Frequency Control; Control
signal used to tune and lock to the
correct frequency
AGC Automatic gain control (feedback)
signal to the tuner. This circuit ensures
a constant output amplitude
regardless of the input amplitude
AM Amplitude Modulation; A "data
encoding to a carrier" method, such
that the carrier amplitude is
proportional to the data value
AP or A/P Asia Pacific
AR Aspect Ratio: 4 by 3 or 16 by 9
ASD Automatic Standard Detection
AV External Audio Video
B-SC1-IN Blue SCART1/EXT1 in
B-SC2-IN Blue SCART2/EXT2 in
B-TXT Blue TeleteXT
B/G Monochrome TV system. Sound
carrier distance is 5.5 MHz. B= VHF-
band, G= UHF-band
C-FRONT Chrominance front input
CBA Circuit Board Assembly (also called
PCB or PWB)
CL Constant Level: audio output to
connect with an external amplifier
CLUT Colour Look-Up Table
COFDM Coded Orthogonal Frequency Division
Multiplexing: a multiplexing technique,
that distributes the data to be
transmitted, over many carriers
COLUMBUS COLour LUMinance Baseband
Universal Subsystem. IC performing
noise reduction and 2D/3D comb
filtering
ComPair Computer aided rePair. A tool for
diagnosing a TV through a PC
controlled interface
CSM Customer Service Mode
CVBS Composite Video and Blanking Signal;
A single video signal that contains
luminance, colour, and timing
information
DAC Digital to Analogue Converter
DBE Dynamic Bass Enhancement: extra
low frequency amplification
DFU Directions For Use: Owner's manual
DMMI Digital Multi Media Interface
DNR Dynamic Noise Reduction / Digital
Noise Reduction; Noise reduction
feature of the set
DRAM Dynamic RAM; dynamically refreshed
RAM
DSP Digital Signal Processing
DST Dealer Service Tool; Special remote
control designed for dealers to enter
e.g. service mode (a DST-emulator is
available in ComPair)
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