EVM Description and Basics
8
SLAU738 – September 2017
Copyright © 2017, Texas Instruments Incorporated
TLV320AIC3109EVM-K
2.2
Analog Signals
2.2.1
Analog Inputs
The analog inputs to the EVM can be connected through two different methods. The analog input sources
can be applied directly to J1 (top or bottom side) or through the analog headers (J10, J13, and J9) around
the edge of the board. The connection details of each header and connector are found in
.
The TLV320AIC3109EVM provides a header in parallel with the input capacitors of each one of the IN1
and IN2 inputs; these headers are provided so end-user can configure the device for DC measurement.
Refer to
TLV320AIC3109-Q1 Automotive, Low-Power, 96-kHz, Mono Audio Codec
for details on the line
input specifications.
In addition to the IN1 and IN2 line input connectors, the EVM features an onboard microphone and a
mono jack for an external microphone, both connected to IN1P input. When the onboard microphone is
used, header J8 must be shorted and J9 should not be connected. Similarly, when external mic is used,
J8 should be disconnected. Both microphones are biased to the MICBIASIN bias signal, that can be
selected with header J7 from either internal mic bias of the audio codec or an external source connected
to J6. Details about the location of the analog inputs of the TLV320AIC3109EVM are shown in
.
2.2.2
Analog Output
The analog outputs to the EVM can be connected through two different methods. The analog outputs are
available from the J1 and J2 (top or bottom) or they may be accessed through J16, J17, J20, and J21 at
the edges of the board. The connection details can be found in Appendix A.
The line outputs of the TLV320AIC3109-Q1 include the recommended low pass filter to remove the out-of-
band noise that can affect the performance of the receiver device. The headphone output of the EVM
includes a low pas filter used for test equipment measurement, available in HPCOM_LPF and
HPOUT_LPF test points. Headers J18 and J19 are used to bypass the AC-coupling capacitors of the
headphone output so the headphone output terminal can be used in Capless mode. In addition to the
headphone output terminal, a mono jack connector (J16) is included to connect a mono headphone with a
typical 3.5mm connector. This jack can be configured to support either AC-Couple or Capless mode by
changing the position of switch SW1. The selection on the headphone output mode should match with the
configuration of the audio codec. Refer to section
for more details on the headphone output
mode configuration. The analog output section of the EVM is shown in
