akira CT-14XA9A, Service Manual

Page: 38 / 76

38
Model No: CT-14XA9A
Version 1.0
Fig. 11 Schematic Diagram (One Switch)
Ratings
Limiting values in accordance with the Absolute Maximum System(IEC 134)
Supply voltage (with reference to V
DD
) V
EE
--18 to + 0,5 V
Note
To avoid drawing V~ current out of terminal Z, when switch current flows into terminals Y, the voltage
drop across the bidirecctional switch must not exceed 0,4 V. If the switch current flows into terminal Z,
no V
DD
current will flow out of terminals Y, in this ease there is no limit for the voltage drop across the
switch, but the voltages at Y and Z may not exceed V
DD
or V
EE
3 Sound power amplifier TDA7057AQ
TDA7057AQ
2x8W Stereo BTL Audio Output Amplifier with DC Volume Control
(1) Features
• DC volume control
• Few external components
• Mute mode
• Short-circuit proof
• No switch -on and switch – off clicks
• Good overall stability
• Low power consumption
• Low HF radiation
• ESD protected on all pins
(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, Thermal protection 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 I00 mA
allows for single-ended headphone applications.