SLOS938F May 2016 – January 2020 TPA3136AD2 , TPA3136D2
PRODUCTION DATA.
The PLIMIT operation will, if selected, limit the output voltage level to a voltage level below the supply rail. In this case, the amplifier operates as if it was powered by a lower supply voltage, and thereby limiting the output power by voltage clipping. PLIMIT threshold is set by the PLIMIT pin voltage.
The PLIMIT circuit sets a limit on the output peak-to-peak voltage. The limiting is done by limiting the duty cycle to a fixed maximum value. The limit can be thought of as a "virtual" voltage rail which is lower than the supply connected to PVCC. The "virtual" rail is approximately four times the voltage at the PLIMIT pin. The output voltage can be used to calculate the maximum output power for a given maximum input voltage and speaker impedance.
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