EN 86
7.
LX9000R
Circuit Diagrams and PWB Layouts
Block diagram and operation
clock
generator
output 1
output 2
output 3
output 4
output 5
output 6
input 1
input 2
input 3
input 4
input 5
input 6
freq_hop
301.35 / 350 kHz
DC
detection
err
temp
NTC
TDA8920
TDA8920
TDA8920
output 1
input 1
TDA8920
SINGLE ENDED 6 x 75W
BRIDGE 3 x 100W
+
-
input 2
TDA8920
+
-
input 3
TDA8920
+
-
clock
generator
freq_hop
301.35 / 350 kHz
DC
detection
err
temp
NTC
output 2
output 3
• clock oscillator
The clock frequency is generated around IC7600. Using 2 extra transistors (7602 and 7608) and 2 ceramic resonators it can be operated at
2 frequencies: 602.7kHz and 700kHz. The frequency is selected by the signal “FREQ_HOP” coming from connector 1302 pin 9.
When FREQ_HOP is low, the output of 7600-1 will be high. This switches transistor 7602 on, and connects resonator 1600 (602.7kHz) to inverter
7600-3. Similarly, when FREQ_HOP is high, resonator 1601 is connected to 7600-3.
The output frequency is divided by two by IC7607, resulting in 301.35kHz or 350kHz.
The purpose of a selectable clock frequency is related to the disturbance of the tuner which is built-in together with this amplifier. In MW, the
software of the set microprocessor will select the other clock frequency in case the amplifier clock interfers with the tuned station.
• Class-D amplifier TDA8920 and low-pass filter
The TDA8920 is a two channel audio power amplifier using class-D technology. The audio input signal is converted into a digital Pulse Width
Modulated (PWM) signal via an analog input stage and PWM modulator. It is then fed to the power stage which outputs a high power PWM
signal which switches between the main supply lines.
The TDA8920 is followed by a 2nd-order low-pass filter. It has a cut-off frequency around 50kHz and converts the PWM signal into analog audio
signal across the loudspeaker.
The TDA8920 has a temperature protection and a current limiter built-in.
Furthermore, via the mode input, the IC can be put in active-, mute- and standby mode.
- Active mode (amplifier fully operational) with output signal.
- Mute mode; the amplifiers are operational, but the audio signal is muted.
- Standby mode; with a very low supply current, the output stage is switched off.
• DC-detection
The DC-detection circuit monitors all 6 outputs for DC. Whenever one or more outputs contain DC for more than 1 second, the circuit will be
activated. A positive voltage will activate transistor 7710 and pin 10 of connector 1302 will be pulled down. In case of a negative voltage, transistor
7716 will be activated, which in turn activates 7710. The set microprocessor will take further action.
MECHANICAL PARTS LIST & SCREWS
8
4822 492 11735
SPRING, TRANSISTOR
9
-
D2.3 x 8
Note:
Only the parts mentioned in this list are normal service
spare parts.
3104 217 07180 bl110
MECHANICAL EXPLODED VIEW
Содержание LX9000R/22
Страница 58: ...Diagnostic Software DVD EN 58 LX9000R 5 ...
Страница 101: ...EN 101 7 LX9000R Circuit Diagrams and PWB Layouts TR 06012_001 040203 F8008 F843 I818 uP Sub Board top view ...
Страница 108: ...EN 108 7 LX9000R Circuit Diagrams and PWB Layouts DVIO BOARD top view ...
Страница 109: ...EN 109 7 LX9000R Circuit Diagrams and PWB Layouts DVIO BOARD top view ...
Страница 110: ...EN 110 7 LX9000R Circuit Diagrams and PWB Layouts DVIO BOARD top view ...
Страница 111: ...EN 111 7 LX9000R Circuit Diagrams and PWB Layouts TEST POINTS OVERVIEW DVIO BOARD ...
Страница 122: ...EN 122 7 LX9000R Circuit Diagrams and PWB Layouts TR 06014a_001 180203 DIGITAL BOARD 1 5 top view ...
Страница 123: ...EN 123 7 LX9000R Circuit Diagrams and PWB Layouts DIGITAL BOARD 1 5 top view TR 06014b_001 120203 ...
Страница 125: ...EN 125 7 LX9000R Circuit Diagrams and PWB Layouts TR 06015a_001 250203 DIGITAL BOARD 1 5 bottom view ...
Страница 126: ...EN 126 7 LX9000R Circuit Diagrams and PWB Layouts TR 06015b_001 180203 DIGITAL BOARD 1 5 bottom view ...
Страница 137: ...Circuit IC descriptions and list of abbreviations EN 137 LX9000R 9 9 3 5 Video routing Figure 9 1 Video IO Europe ...
Страница 141: ...Circuit IC descriptions and list of abbreviations EN 141 LX9000R 9 9 4 4 Video routing Figure 9 3 Video IO Nafta ...
Страница 146: ...Circuit IC descriptions and list of abbreviations EN 146 LX9000R 9 9 6 2 Block Diagram Block Diagram DVIO1 8 Figure 9 7 ...
Страница 151: ...Circuit IC descriptions and list of abbreviations EN 151 LX9000R 9 Figure 9 11 ...
Страница 152: ...Circuit IC descriptions and list of abbreviations EN 152 LX9000R 9 Figure 9 12 ...
Страница 156: ...Circuit IC descriptions and list of abbreviations EN 156 LX9000R 9 IC7411 ...
Страница 161: ...Circuit IC descriptions and list of abbreviations EN 161 LX9000R 9 ...
Страница 162: ...Circuit IC descriptions and list of abbreviations EN 162 LX9000R 9 ...
Страница 163: ...Circuit IC descriptions and list of abbreviations EN 163 LX9000R 9 ...
Страница 181: ...Circuit IC descriptions and list of abbreviations EN 181 LX9000R 9 9 10 4 IC s Divio 1 8 IC7400 uPD72852 ...
Страница 182: ...Circuit IC descriptions and list of abbreviations EN 182 LX9000R 9 ...
Страница 183: ...Circuit IC descriptions and list of abbreviations EN 183 LX9000R 9 ...
Страница 184: ...Circuit IC descriptions and list of abbreviations EN 184 LX9000R 9 ...
Страница 185: ...Circuit IC descriptions and list of abbreviations EN 185 LX9000R 9 IC7431 uPD72893 ...
Страница 186: ...Circuit IC descriptions and list of abbreviations EN 186 LX9000R 9 ...
Страница 187: ...Circuit IC descriptions and list of abbreviations EN 187 LX9000R 9 ...
Страница 188: ...Circuit IC descriptions and list of abbreviations EN 188 LX9000R 9 ...
Страница 189: ...Circuit IC descriptions and list of abbreviations EN 189 LX9000R 9 ...
Страница 190: ...Circuit IC descriptions and list of abbreviations EN 190 LX9000R 9 ...
Страница 191: ...Circuit IC descriptions and list of abbreviations EN 191 LX9000R 9 ...
Страница 192: ...Circuit IC descriptions and list of abbreviations EN 192 LX9000R 9 ...
Страница 193: ...Circuit IC descriptions and list of abbreviations EN 193 LX9000R 9 ...
Страница 194: ...Circuit IC descriptions and list of abbreviations EN 194 LX9000R 9 ...
Страница 195: ...Circuit IC descriptions and list of abbreviations EN 195 LX9000R 9 ...
Страница 196: ...Circuit IC descriptions and list of abbreviations EN 196 LX9000R 9 ...
Страница 197: ...Circuit IC descriptions and list of abbreviations EN 197 LX9000R 9 ...
Страница 198: ...Circuit IC descriptions and list of abbreviations EN 198 LX9000R 9 IC7802 uPD78F0988A ...
Страница 199: ...Circuit IC descriptions and list of abbreviations EN 199 LX9000R 9 ...
Страница 200: ...Circuit IC descriptions and list of abbreviations EN 200 LX9000R 9 ...
Страница 201: ...Circuit IC descriptions and list of abbreviations EN 201 LX9000R 9 ...
Страница 202: ...Circuit IC descriptions and list of abbreviations EN 202 LX9000R 9 ...
Страница 203: ...Circuit IC descriptions and list of abbreviations EN 203 LX9000R 9 ...
Страница 204: ...Circuit IC descriptions and list of abbreviations EN 204 LX9000R 9 ...
Страница 205: ...Circuit IC descriptions and list of abbreviations EN 205 LX9000R 9 IC7605 BU2288FV ...
Страница 206: ...Circuit IC descriptions and list of abbreviations EN 206 LX9000R 9 ...
Страница 207: ...Circuit IC descriptions and list of abbreviations EN 207 LX9000R 9 IC7604 BA7082F ...
Страница 208: ...Circuit IC descriptions and list of abbreviations EN 208 LX9000R 9 ...
Страница 209: ...Circuit IC descriptions and list of abbreviations EN 209 LX9000R 9 ...
Страница 210: ...Circuit IC descriptions and list of abbreviations EN 210 LX9000R 9 ...
Страница 220: ...EN 220 10 LX9000R Spare Parts List 322 327 330 323 328 331 324 339 1 339 2 339 4 340 2 340 1 339 3 339 5 ACCESSORIES ...