Power Amplifier (LA4620)
The power amplifier is a
Internal Diagram of LA4620
IN11+ | 3 | + |
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| Input | ||
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IN11- | 5 |
| Amp. |
- |
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IN12- | 4 | - |
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| Input | ||
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| + | Amp. |
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| Terminal |
PriGND | 6 |
| Protection |
| Circuit | ||
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IN21+ | 9 | + |
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| Input | ||
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IN21- | 7 |
| Amp. |
- |
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IN22- | 8 | - |
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| Input | ||
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| Amp. |
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| + |
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| 16 | 2 |
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| NC | DC |
Amp.
RL Short
Protector
Amp.
Ripple
Filter
Amp.
RL Short
Protector
Amp.
10
MUTE
Power
Amp.
Power
Amp.
Pop Noise
Prevention
Circuit
Power
Amp.
Power
Amp.
1113
VCC2 ADJ
19Boot11
20 OUT11
21PoGND1
22 OUT12
23 Boot21
1 VCC1
18Boot21
17OUT21
15PoGND2
14OUT22
12Boot22
Power Supply Circuit
The power supply circuit generates six voltages as shown in the following table. VDD voltage is always generated. The others are controlled by APO signal from the CPU.
Name | Voltage | For operation of |
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VDD | +5.1V | CPU, Reset IC, Gate array, Working strage RAM |
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DVDD | +5.3V | DSP, Key touch LSI, Sound source ROM, Effect RAM, DAC |
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AVDD | +5.2V | DAC, Filter |
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LVDD | +5.2V | LED driver |
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VCC | +12V | Pilot lamp |
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VD | +12V | Power amplifier |
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