RCA MCR51R410, Service Manual

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SERVICE MANUAL
1.5 Sound power amplifierTDA7057AQ
1.5.1 Features
DC volume control
Few external components
Mute mode
Thermal protection
Short-circuit proof
No switch-on and switch-off clicks
Good overall stability
Low power consumption
Low HF radiation
ESD protected on all pins.
1.5.2 General Description
The TDA7057AQ is a stereo BTL output
amplifier with DC volume control. The device is
designed for use in TVs and monitiors, but is
also suitable for battery-fed portable
recorders and radios.
Missing Current Limiter (MCL)
A MCL protection circuit is built-in. The MCL
circuit is activated when the difference in
current between the output terminal of each
amplifier exceeds 100 mA (typical 300 mA).
This level of 100 mA allows for single-ended
headphone applications
.
1.5.3 Block Diagram
.
Fig.13
1.5.4 Refer to Table 7 about Functions and Service Data of TDA7057AQ’s Pins.
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