TA2021-100 ETC1 [List of Unclassifed Manufacturers], TA2021-100 Datasheet - Page 9

• Manufacturer Part Number: TA2021-100
• Description: STEREO 100W (4-ohm) CLASS-T DIGITAL AUDIO AMPLIFIER DRIVER USING DPP-TM TECHNOLOGY
• Manufacturer: ETC1 [List of Unclassifed Manufacturers]

T E C H N I C A L I N F O R M A T I O N
The TA2021-100 will quickly automatically come out of mute when it detects that the input
signal has gone above the preset level.
Input Limit
To “soften” the clipping characteristics of the TA2021-100 it will limit the audio signal to a pre-
determined, programmable input-limit level according to the voltage on the MIS/ADDR pin as
specified in the previous table. This limit is a percentage of the maximum possible output level.
Overload
When logic low, the OVRLD/SCL pin indicates that the level of the input signal has overloaded
the amplifier and that the audio output signal is starting to distort. The OVRLD/SCL signal is
active only while an overload is present. The OVRLD/SCL signal can be used to control a
distortion indicator light or LED through a simple buffer circuit.
Sleep
When a logic high signal is supplied to SLEEP, both amplifier channels are shut down and the
TA2021-100 is put into a low quiescent-current mode. When a logic level low is supplied to
MUTE, both amplifiers are fully operational.
Volume Control
A 5 M
potentiometer is used between V2BG, DCVOL and AGND (analog ground) to control
the output volume of both channels. When DCVOL is at the same level as V2BG, the output
volume is at –6 dB. When DCVOL is at the same level as GND, the output volume is at the
minimum, or –119.5 dB.
Auxiliary Outputs
The outputs AUXOUT1 and AUXOUT2 are analog-signal audio outputs in which the signal level
is controlled by the volume control. These outputs are capable of driving approximately 15mW
each into 20-ohm loads. These outputs are still active when the TA2021-100 is in mute mode,
even if the TA2021-100 is muted because no speaker is connected (see next section).
Speaker Detect
On power-up the TA2021-100 checks to make sure that speakers are connected to prevent
damage. If a speaker is not detected on either channel on power-up, the TA2021-100 keeps the
output stages of both amplifiers shut down (in mute) and signifies this fact by asserting a logic
level one on HMUTE/SDA. The TA2021-100 will come out of mute when speakers are
connected, even after a relatively long period of time (minutes after power-up).
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