Texas Instruments TPA0142, Руководство пользователя

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Using The TPA0142 EVM With the Plug-N-Play Evaluation Platform
3-10 Details
3.3.2.1 S1 — Shutdown Switch
Pushbutton switch S1 on the EVM allows the manual shutdown of the
TPA0142 amplifier IC.
3.3.2.2 S3 — Output Mode Jumper
To keep the module amplifier IC in the single-ended output mode regardless
of the module control input state, set jumper S3 to ON.
Jumper S3 connects the SE/BTL output mode control input pin on the amplifier
IC directly to V
DD
, so that when S3 is ON, the IC is held in the single-ended
output mode regardless of the state of the SE/BTL module control input. When
S3 is OFF, a pulldown resistor on the module holds the IC output mode control
input pin low, keeping the IC in the BTL output mode.
The TPA0142 amplifier IC has two separate inputs for each channel. An
internal multiplexor selects which input will be connected to the amplifier
based on the state of the SE/BTL pin on the IC.
3.3.2.3 TP1 — PCB ENABLE
Leave PCB ENABLE test point, TP1, tied to ground or floating for normal
operation.
The PCB ENABLE input is active-high and is used when the signal level
applied to the PC BEEP signal input pin (TP2) does not have sufficient
peak-to-peak voltage to trigger the auto-detect function. When TP1 is pulled
high, the PC BEEP input is active. See the TPA0142 amplifier data sheet for
additional information.
3.3.2.4 TP2 — PC BEEP SIgnal Input Pin
Leave PC BEEP signal input test point, TP2, floating, for normal operation.
The TPA0142 amplifier IC monitors this input for a signal when it is operating
in both the active and shutdown modes. When a signal is detected, the IC
automatically switches to this input and applies the signal to
both channels.
When the signal ends, the IC switches back to the line inputs. The gain of this
input is approximately
¼
V/V. See the TPA0142 amplifier data sheet for
additional information.