Texas Instruments TPA0152 User Manual page 27

3.3.2.7 UP and DOWN Signal Input Pins
Leave the UP and DOWN signal input pins floating for normal operation.
If external control signals are to be used, set jumpers J3 and J4 to OFF and
connect the control lines to the UP and DOWN signal input pins. When the
desired line is pulled low for four clock cycles, the volume will increment by one
step, followed by a short delay. This delay will decrease the longer the line is
held low, eventually reaching a delay of zero.
3.3.2.8 CLK IN Signal Input Pin
Leave the CLK IN signal input pin floating for normal operation.
The amplifier may be controlled by an external microprocessor clock at a
speed of up to 45 kHz when the jumper J2 is set to OFF and the external clock
signal line is connected to the CLK IN signal input pin. Note that the internal
delay between volume level increments is disabled during microprocessor
mode.
Using The TPA0152 EVM With the Plug-N-Play Evaluation Platform
Details
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