Monolithic Linear IC
Car Radio/Car Stereo 5 W
LA4485
Overview
The LA4485 obviates the need for the BS capacitor, noise filter capacitor, and oscillation prevention RC components previously required by power amplifier ICs by integrating them on the IC itself. The LA4485 requires only the barest minimum of external components and both dual and BTL type operation are supported in the power series ("stylish power").
Functions
■Dual: 5 W 
2, BTL: 15 W
■Extremely few external components required: 4 or 5 in dual mode, 3 or 4 in BTL mode
■
◆Overvoltage protection circuit
◆Thermal protection circuit
◆Output DC short protection circuit (with respect to both VCC and ground) ■ Circuit to handle application of +VCC to the outputs
■
■ Package: SIP13H
Block Diagram
Monolithic Linear IC
Car Radio/Car Stereoereo 55 WW PowerPower AmplifierAmplifier thatthat RequiresRequires Minimal Externall ComponentsComponents
LA4425AC 5A
Overview
The LA4425A is a 5 W power amplifier IC for car radio and car stereo systems that requires an extremely small number of external components.
Functions
■The industry's first power amplifier that requires so few external components ◆ Provided in the industry's smallest package:
■As a power IC, evaluation, adjustment, and investigation are essentially unnecessary This leads to simplified management
■Wide operating supply voltage range: 5 to 16 V
■
◆Overvoltage protection circuit
◆Thermal protection circuit
◆Output DC short protection circuit ■
Block Diagram
Channel 1 input
Small signal system ground
BTL IN
Channel 2 input
| Large signal | Small signal |
Filter | system VCC | system VCC |
| 6 |
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| 7 | 8 |
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| Filter |
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| Short to ground |
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1 | Input |
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| protection circuit |
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| Output | 13 | |||||
| amplifier |
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| amplifier |
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| amplifier | ||||
| (CH1) |
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| Rf1 |
| Short to VCC |
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| protection circuit |
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| RNF1 |
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| Thermal protection |
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| circuit |
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3 | REF |
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| 12 | |
amplifier |
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| RNF2 | Rf2 |
| Overvoltage |
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| protection circuit |
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4 |
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| Short to VCC |
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Input |
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| protection circuit |
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| Output | 11 | |||||
| amplifier |
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2 | amplifier |
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| amplifier | ||||
(CH2) | Short to ground | |||||||
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| protection circuit |
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| Standby mode |
| MUTE |
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| switch |
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| 5 |
| 9 |
| 10 |
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| BTL OUT | Standby mode | MUTE |
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Channel 1 output
Large signal system ground
Channel 2 output
| VCC 13.2V |
| + |
| 1000∝F |
5 |
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Ci 2.2∝F |
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+ |
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1 | Co 1000∝F |
| |
LA4425A | + |
4 | |
2 | speaker |
| 4Ω |
3 |
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| 59 Car Audio | 60 Car Audio |
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