TCD6000 Datasheet, PDF (31/36 Pages) Tripath Technology Inc. – 6 CHANNEL CLASS-T DIGITAL AUDIO PROCESSOR USING DIGITAL POWER PROCESSINGTM TECHNOLOGY

OUTPUT CHARACTERISTICS
Tripath Technology, Inc. – Preliminary Technical Information
The TCD6000 outputs consist of six pairs of complementary 1-bit digital data streams, one pair per audio
channel. They switch from 0V to 5V (+/- 10%) and constitute a pulse-density-modulated (PDM) form of the
audio signal. They are used to drive Tripath power stages in a switching amplifier configuration.
The output power of a power stage can be expressed as V² /R, V being the voltage amplitude of the power
stage output and R the speaker input impedance, typically 4 to 8 ohms.
The audio signal is recovered by filtering the PDM signal through an LC filter located at the inputs of the
speaker. The following figure shows the power stage output waveform and the filtered signal at the speaker
inputs:
Typical waveform at power stage output
Typical waveform at speaker inputs after LC filtering
TCD6000 outputs are pulse density modulated outputs. Their frequency varies constantly over time and can
typically reach a maximum value of 800 kHz.
A Mute output (HMUTE) can be connected to all 6 power stages to force them into a tri-state mode when a
hard mute condition is encountered. The HMUTE output can be programmed to be either active-high or
active-low (bit D6 in control register 74h).
An overload is detected whenever the combination of input signal amplitude and volume programmed in the
TCD6000 results in output signal saturation and distortion. The OVRLDB pin goes active low when this
condition occurs.
A test output pin is also provided (TST_EN) for external testing purposes. Setting bit D4 in control register
74h will force this output to an active high state.
The HMUTE, OVRLDB and TST_EN outputs are 5V digital outputs.
The TCD6000 also includes a pair of stereo headphone outputs (HP1 and HP2), which are connected to
channels 1 and 2. These outputs are analog with maximum 3V peak-to-peak amplitude. They have a
common mode voltage of 2V and should therefore be AC coupled to the headphone jack. If the headphone
outputs are not being used, these pins may be left unconnected.
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TCD6000 – Rev. 1.0/09.04